Celstran - Hi Polymers brochure... · 1.2 Quality Management Celstran is a unit of Ticona, ......
Transcript of Celstran - Hi Polymers brochure... · 1.2 Quality Management Celstran is a unit of Ticona, ......
Long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
Cel
stra
n® C
om
pel
® L
ong-
fibre
-rei
nfor
ced
ther
mop
last
ics (
LFT
)
• markedly highermechanical properties
• high notchedimpact strength
• reduced creep tendency• very good stability
over a broad range oftemperatures andclimatic conditions
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
1. Introduction 4
1.1 General information 41.2 Quality Management 51.3 Brief description 5
2. Grades 7
2.1 Overview of grades 72.2 Survey and nomenclature of Celstran 82.3 Survey and nomenclature of Compel 82.4 Form supplied 92.5 Colours 9
3. Material Data 10
4. Physical Properties 20
4.1 General information 204.2 Mechanical properties 214.2.1 Preliminary remarks 214.2.2 Short-term stress 214.2.3 Creep properties 234.2.4 Toughness 254.2.5 Fatigue 264.2.6 Surface properties 264.3 Thermal properties 274.3.1 Coefficient of expansion 274.3.2 Specific heat, enthalpy 274.3.3 Thermal conductivity 284.4 Electrical properties 284.5 Optical properties 294.6 Acoustic properties 29
5. Environmental Effects 30
5.1 Thermal properties 305.1.1 Heat deflection temperature 305.1.2 Heat ageing 305.2 Flammability 315.3 Chemical resistance 325.4 Weathering and UV resistance 32
® = registered trademark
Table of Contents
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Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
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6. Processing 33
6.1 Preparation 336.2 Injection moulding of Celstran 33
including mould making6.2.1 Machine requirements 336.2.2 Processing conditions 346.2.3 Flow properties and flow path lengths 366.2.4 Shrinkage 366.2.5 Gate and mould design 386.2.6 Special methods 386.3 Blow moulding of Celstran 396.3.1 Materials 396.3.2 Machine requirements 406.3.3 Parison die 406.3.4 Temperatures 406.4 Extrusion of Celstran 416.5 Processing of Compel 416.5.1 Plasticizing/compression moulding 416.5.2 Other methods 426.6 Safety notes 42
7. Finishing 43
7.1 Machining 437.2 Assembly 437.2.1 Welding 437.2.2 Adhesive bonding 45
8. Recycling 46
9. Photo supplement showing typical applications 47
10. Subject Index 51
11. Literature 53
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11Literature
Introduction
Grades
Material Data
Physical Properties
Environmental Effects
Processing
Finishing
Recycling
Photo supplement showing typical applications
Subject Index
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
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These materials have substantially better mechanicalproperties than comparable short-fibre-reinforced thermoplastics. The long-fibre-reinforced thermo-plastics are thus suitable for the manufacture ofmouldings that are subject to high mechanical stress –even at elevated temperatures – and for products thathave in the past been made of cast metals or thermo-sets.
The most important field of application at present forCelstran is the automotive sector [3]. For example,gear levers and sunroof drainage channels are madefrom it because of the mechanical stress imposed onthem. Parts near the engine such as fan shrouds, fig.1.4, engine noise deadening casings, fig. 1.5, or hous-ings for electronic engine control systems, fig. 1.6,also have to withstand additional temperature stress.
Fig. 1.3 · Cross-section through a Celstran PP-GF50 pellet, a PP reinforced with
50% by weight long glass fibres
Short-fibre pelletfibre length = 0.2 to 0.4 mm
Wire coating
Fully impregnatedlong-fibre pelletfibre length= 10 to 25 mm
Celstran ®Compel ®
Fig. 1.2 · Diagram of a fully impregnated long-fibre pellet (right) compared with
wire coating (centre) and short-fibre pellets (left)
1. Introduction
1.1 General information
Celstran and Compel are long-fibre-reinforced ther-moplastics (LFT) made by Ticona. Various processingmethods are used to produce high-strength compo-nents from these materials, which are tailor-made tocustomers' requirements (fig. 1.1). Almost all partial-ly crystalline and amorphous thermoplastics are sui-table as thermoplastic matrix materials.
These grades are produced in a special patented pultrusion process [1]. The fibres incorporated in thisprocess can be glass, carbon, aramid or stainless steel.In pultrusion the continuous filaments are pulledthrough the thermoplastic melt. Process control anddie are optimized so that
- high impregnation quality without damage to thefibres is achieved and
- the individual filament of the reinforcing fibres isthoroughly wetted [1, 2], fig. 1.2 and 1.3.
Fig. 1.1 · Celstran and Compel are starting materials for high-strength components
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
1.2 Quality Management
Celstran is a unit of Ticona, Kelsterbach and is re-gistered to ISO 9001. QS-9000 certification is sched-uled until end of 2000.
The quality system and the associated documentationare constantly being developed. The basis for this isVDA vol. 6, 4th edition, 1998, QS-9000 and anannual self-assessment in accordance with the criteriamodel of the European Quality Award (EQA) of theEuropean Foundation of Quality Management.
To foster effective partnerships with our customersTicona offers to conclude quality agreements and alsoto issue test certificates. These agreements documentthe specifications for our products. 3.1B certificates inaccordance with EN 10 204 can be arranged for eachconsignment.
1.3 Brief description
The most important application properties of thelong-fibre-reinforced thermoplastics compared withthe corresponding short-fibre-reinforced materials are
- markedly higher mechanical properties- higher notched impact strength- reduced creep tendency- very good stability at elevated temperatures in
humid conditions.
Celstran is the trademark for long-fibre-reinforcedthermoplastics. They are supplied in form of cylindri-cal moulding granules (typical geometry: diameter 3 mm, length up to 12 mm), in which fibre length andpellet length are identical.
The range of Celstran products comprises a numberof possible matrix-fibre combinations. They areintended for injection moulding, extrusion and blowmoulding and produce moulded parts with markedlygreater fibre lengths than conventional short-fibre-reinforced plastics.
Celstran mouldings display fracture behaviour typicalof long-fibre reinforcement. This is demonstratedwhen the fibre length exceeds a critical value. Thisvalue depends on the fibre-matrix combination; prac-tical experience shows that it is between 0.8 and 3 mm. Above this fibre length the material has thecharacteristics of a fibre composite [1].
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Fig. 1.4 · Fan shroud made from Celstran PP-GF40for the BMW E38 and E39 diesel vehicles
(manufacturer: Geigertechnik GmbH, Garmisch Partenkirchen, Germany)
Fig. 1.5 · Engine noise deadening casing made from Celstran PP-GF40 for the Porsche Boxster
(manufacturer: Mürdter, Mutlangen, Germany)
Fig. 1.6 · Housing made from Celstran PP-GF40 for the electronic engine control system of theMercedes Benz Roadster “SLK” (manufacturer:
Kostal GmbH & Co.KG, Lüdenscheid, Germany)
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long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
The long-fibre reinforcement is manifested by thefibre skeleton whose outer shape remains unchangedafter the resin matrix is burned off, fig. 1.7. This fibre skeleton is responsible among other things forthe good impact strength; it absorbs the impact ener-gy and dissipates it in the moulding. The long-fibrereinforcement also has a beneficial effect on the pro-perties at elevated service temperatures and on thecreep properties.
Celstran SF grades are masterbatches with 50 to 60%by weight stainless steel filaments [4, 5]. They areused to produce housings with electromagnetic shiel-ding properties and antistatic components, see sup-plement [4] (will be mailed upon request).
Compel is the trademark for even longer pellets (typical length: 25 mm). When processed, they are plasticized gently and then compression-moulded.This gentle process yields higher impact strength andenergy absorption than injection moulding, particu-larly with large-area structural components, fig. 1.8.Processing of Compel by plasticizing/compressionmoulding offers the following advantages comparedwith e.g. GMT compression moulding:
- freedom of shaping without the use of cut outs- low energy requirement due to screw plasticizing- low moulding pressure required- very good melt flowability- uniform glass fibre content even in thin ribs- good moulded part surfaces- immediate recycling of production waste.
For further details of Compel please order ourCompel brochure.
Fig. 1.8 · Instrument panel carrier for a car made from Compel PP-GF30 by plasticizing/
compression moulding
Fig. 1.7 · After burning off, a moulding (example: pump head made from Celstran
PA66-GF50, top) retains its geometry almost intact as a fibre skeleton (bottom)
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Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
2. Grades
2.1 Overview of grades
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Celstran
Material Glass fibres Filaments of stainless Carbon fibres Aramid fibreshigh-grade steel
PP PP-GF30-04 PP-SF60PP-GF30-05PP-GF40-04PP-GF40-05PP-GF50-04PP-GF57-05
PE-HD PE-HD-GF60-01
PA66 PA66-GF40-01 PA66-SF50 PA66-CF40-01 PA66-AF35-02PA66-GF40-02PA66-GF50-01PA66-GF50-02PA66-GF60-01PA66-GF60-02
PA PA12-SF50 PA6-CF30
ABS ABS-SF50
PC PC/ABS-GF25-02 PC-SF50PC/ABS-GF40-02
PBT, PET PBT-GF40-01 PBT-SF50PBT-GF50-01PET-GF40-01PET-GF50-01
PPS PPS-GF50-01 PPS-SF 50 PPS-CF40-01 PPS-AF35-01PPS-GF40-01
TPU TPU-GF30-01 TPU-CF40-01TPU-GF40-01TPU-GF50-01TPU-GF60-01
POM POM-GF40-01 POM-SF50 POM-AF30-01
Compel
PP PP-GF30-04PP-GF30-05PP-GF40-04PP-GF40-05PP-GF50-04PP-GF57-05
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
2.2 Survey and nomenclature of Celstran
In the grade designation for Celstran, fig. 2.1,
- the first group of symbols indicates the basic polymer
- the letters after the hyphen indicate the type ofreinforcing fibres
- the number immediately following indicates thefibre content in % by weight
- the pair of numbers appended after the grade desig-nation (modification) indicate special features as viscosity, impact strength, heat stabilization etc.
- the second pair of numbers is an additional suffixfor special formulations like high light stabilization,ease of demoulding, markedly low emission rate etc.
- P with the following numbers characterise the pelletlength and with it the fibre length in mm
- the numbers after the dash symbolize the colourcode. Natural grades have no declaration.
2.3 Survey and nomenclature of Compel
Grades of Compel with polypropylene as matrixmaterial with 30-57% long-glass-fibre reinforcementare currently available.
All Compel grades are heat-stabilized.
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Fig. 2.1 · Grade designation for Celstran
Example: Celstran PP-GF40-0414P10/10
Matrix materialType of fibreFibre content in % (w/w)ModificationAdditional suffixPellet length in mmColour
Key to abbreviations:
Matrix materials:
PP PolypropylenePA66 Polyamide 66PA6 Polyamide 6PA12 Polyamide 12PBT Polybutylene terephthalatePC PolycarbonatePE-HD High-density polyethylenePET Polyethylene terephthalatePOM PolyoxymethylenePPS Polyphenylene sulphideTPU Thermoplastic polyurethaneABS Acrylonitrile-butadiene-styrene
Fibres:
GF GlassCF CarbonAF AramidSF Stainless steel
Modification of Celstran PP:
03 chemically coupled, heat stabilized04 chemically coupled, heat stabilized,
increased flowability05 chemically coupled, heat stabilized,
high impact modificated
Modification of Celstran PA:
01 high gloss02 heat stabilized10 flame-retardant
(V-0 in accordance with UL 94)
Modification of Celstran PE-HD:
01 chemically coupled
Additional suffix:
16 easily demouldable05 highly light-stabilized53 markedly low C emission55 markedly low C emission and light stabilized
Colours:
without natural 50-59 yellow10-19 black 60-69 brown20-29 white 70-79 green30-39 grey 80-89 blue40-49 red 90-99 specialities
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
2.4 Form supplied
To a large extend Celstran and Compel are suppliedto individual requirements both in terms of the thermoplastic matrix and of the fibres used for rein-forcement. Possible matrix systems are
- high-density polyethylene, PE-HD- polypropylene, PP- polyacetal, POM (Hostaform®)- polybutylene terephthalate, PBT (Celanex®)- polyethylene terephthalate, PET (Impet®)- polyphenylene sulphide, PPS (Fortron®)- thermoplastic polyurethane, TPU- acrylonitrile-butadiene-styrene copolymer, ABS- polycarbonate, PC, and PC blends with ABS- polyamide 66, PA66- polyamide 6, PA6- polyamide 12, PA12.
Other matrix systems are being prepared.
The following reinforcing fibres are available:
- glass- carbon- aramid- stainless steel filaments.
Celstran is supplied in 25-kg bags and 500-kg largecontainers.
Silo truck delivery is also possible (à 20 t) withCelstran. Because of the high impregnation of the fibres pneumatic conveyance is possible.
Compel is supplied in 20-kg bags and 400-kg large containers.
2.5 Colours
Celstran PP and Compel PP are normally supplied in natural and black. In-house coloration by the pro-cessor is not recommended because of the need forgentle plasticization.
Coloration of Celstran PP and Compel PP is subject to limitations; colours on request. Celstran PA can be supplied coloured.
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long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
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3. Material DataPhysical property Unit Test method Test specimen
Content of reinforcing material % by wt. ISO 3451, part 1 No test specimen (pellets)
Density g/cm3 ISO 1183 10 x 10 x 4 mm
Water absorption at 23°C after 24 h % by wt. ISO 62 80 x 80 x 1 mm
Mechanical properties, measured under standard conditions, ISO 291-23/50
Tensile strength at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile strength at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 23°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 80°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile modulus at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Tensile modulus at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Flexural strength at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strength at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 23°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 80°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at 23°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at -30°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Puncture energy at 23°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Puncture energy at -30°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Maximum force N ISO 6603 part 2 60 x 60 x 2 mm
Thermal properties
Heat deflection temperature HDT/A (1.8 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Heat deflection temperature HDT/C (8.0 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Celstran® Compel®
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long-fibre-reinforced thermoplastics (LFT)
PP-GF30-04 PP-GF30-05 PP-GF40-04 PP-GF40-05 PP-GF50-04 PE-HD-GF60-01
30 30 40 40 50 60
1.12 1.12 1.22 1.22 1.33 1.51
– – – – – –
95 75 110 100 125 90
52 – 63 – 70 –
2.3 2.8 2 2.3 1.8 1.6
2.9 – 2.5 – 2.4 –
7,200 5,300 9,100 7,300 11,700 12,000
4,400 – 6,500 – 7,200 –
160 135 190 155 200 88
95 – 100 – 105 –
2.9 3.7 2.7 3.2 2.4 –
3.7 – 3.6 – 3.2 –
7,000 5,300 9,500 7,100 11,100 9,000
4,800 – 6,400 – 7,200 –
48 60 59 70 59 –
44 – 55 – 57 –
18 23 16 25 19 –
20 – 13 – 14 –
– – – – 296
– – – – – –
3.9 – 4.8 – 6.3 –
4.9 – 5.1 – 6.1 –
– – – – –
148 – 152 – 155 121
122 – 128 – 132 –
Celstran PP Celstran PE-HD
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long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
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Physical property Unit Test method Test specimen
Content of reinforcing material % by wt. ISO 3451, part 1 No test specimen (pellets)
Density g/cm3 ISO 1183 10 x 10 x 4 mm
Water absorption at 23°C after 24 h % by wt. ISO 62 80 x 80 x 1 mm
Mechanical properties, measured under standard conditions, ISO 291-23/50
Tensile strength at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile strength at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 23°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 80°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile modulus at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Tensile modulus at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Flexural strength at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strength at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 23°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 80°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at 23°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at -30°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Puncture energy at 23°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Puncture energy at -30°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Maximum force N ISO 6603 part 2 60 x 60 x 2 mm
Thermal properties
Heat deflection temperature HDT/A (1.8 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Heat deflection temperature HDT/C (8.0 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
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3
Celstran PA66
40 40 40 40 50 50
1.45 1.45 1.44 1.44 1.56 1.56
0.55 0.55 0.55 0.55 0.4 0.4
235 170 230 155 260 190
140 120 135 115 160 130
2.4 2.8 2.2 2.3 2.4 2.5
3 2.9 2.5 2.6 2.4 2.7
14,000 10,200 13,000 8,700 16,200 12,300
8,100 7,500 7,800 7,100 10,500 9,600
370 290 300 245 405 320
250 210 215 195 – –
3.5 4.1 3.2 3.8 3.2 3.8
4.1 3.7 3.4 3.9 – _
12,300 9,800 11,100 8,600 14,800 11,700
7,500 6,800 7,200 6,500 9,500 9,000
85 95 81 91 90 95
75 – 72 65 85 80
30 30 36 36 33 34
30 30 36 37 33 34
230 240 260 300 250 295
220 – 240 280 275 –
8.6 – – – 8.6 –
– – – – – –
4,950 – – – 4,600 –
255 255 242 242 256 256
240 240 218 218 249 249
PA66-GF40-02 PA66-GF40-02 PA66-GF40-01 PA66-GF40-01 PA66-GF50-02 PA66-GF50-02DAM cond. DAM cond. DAM cond.
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
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Physical property Unit Test method Test specimen
Content of reinforcing material % by wt. ISO 3451, part 1 No test specimen (pellets)
Density g/cm3 ISO 1183 10 x 10 x 4 mm
Water absorption at 23°C after 24 h % by wt. ISO 62 80 x 80 x 1 mm
Mechanical properties, measured under standard conditions, ISO 291-23/50
Tensile strength at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile strength at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 23°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 80°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile modulus at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Tensile modulus at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Flexural strength at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strength at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 23°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 80°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at 23°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at -30°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Puncture energy at 23°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Puncture energy at -30°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Maximum force N ISO 6603 part 2 60 x 60 x 2 mm
Thermal properties
Heat deflection temperature HDT/A (1.8 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Heat deflection temperature HDT/C (8.0 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
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50 50 60 60 35 40
1.55 1.55 1.69 1.69 1.22 1.33
0.4 0.4 0.25 0.25 – –
255 175 285 200 115 270
150 120 175 140 – –
2.1 2.4 2.2 2.3 2 1
2.4 2.4 1.9 2 – –
16,500 11,200 19,000 15,200 8,600 30,800
9,800 8,500 15,000 11,900 – –
350 260 410 330 183 440
250 210 – – – –
3.1 3.6 3 3.3 – –
4.5 3.5 – – – –
14,500 8,700 18,000 15,000 7,800 26,000
8,600 7,200 – – – –
96 107 100 100 – –
82 76 – – – –
41 40 45 – 12 21
41 41 – – – –
330 360 280 320 140 255
290 330 280 – – –
– – – – – –
– – – – – –
– – – – – –
242 242 257 257 246 260
217 217 250 250 – –
Celstran PA66
PA66-GF50-01 PA66-GF50-01 PA66-GF60-02 PA66-GF60-02 PA66-AF35-02 PA66-CF40-01DAM cond. DAM cond.
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long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
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Physical property Unit Test method Test specimen
Content of reinforcing material % by wt. ISO 3451, part 1 No test specimen (pellets)
Density g/cm3 ISO 1183 10 x 10 x 4 mm
Water absorption at 23°C after 24 h % by wt. ISO 62 80 x 80 x 1 mm
Mechanical properties, measured under standard conditions, ISO 291-23/50
Tensile strength at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile strength at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 23°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 80°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile modulus at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Tensile modulus at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Flexural strength at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strength at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 23°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 80°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at 23°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at -30°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Puncture energy at 23°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Puncture energy at -30°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Maximum force N ISO 6603 part 2 60 x 60 x 2 mm
Thermal properties
Heat deflection temperature HDT/A (1.8 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Heat deflection temperature HDT/C (8.0 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
17
25 40 40 50 40 50
1.36 1.5 1.65 1.75 1.7 1.8
– – – – – –
120 152 132 166 189 165
– – – – – –
1.8 1.4 1.25 1.3 1.8 1.1
– – – – – –
8,100 12,000 13,500 15,000 15,300 16,000
– – – – – –
185 235 216 262 310 252
– – – – – –
– – – – – –
– – – – – –
7,400 11,000 11,800 13,000 13,700 14,500
– – – – – –
– – – – – –
– – – – – –
– – 28 – 36 –
18 – – – – –
213 182 352 454 267 347
– – – – – –
– – – – – –
– – – – – –
– – – – – –
107 113 213 216 249 249
– – – – – –
Celstran PC/ABS Celstran PBT/PET
PC/ABS-GF PC/ABS-GF PBT-GF PBT-GF PET-GF PET-GF25-02 40-02 40-01 50-01 40-02 50-01
3
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
Physical property Unit Test method Test specimen
Content of reinforcing material % by wt. ISO 3451, part 1 No test specimen (pellets)
Density g/cm3 ISO 1183 10 x 10 x 4 mm
Water absorption at 23°C after 24 h % by wt. ISO 62 80 x 80 x 1 mm
Mechanical properties, measured under standard conditions, ISO 291-23/50
Tensile strength at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile strength at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 23°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Elongation at break at 80°C % ISO 527 part 1/2; Multi-purpose test specimentest speed 5 mm/min to ISO 3167
Tensile modulus at 23°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Tensile modulus at 80°C MPa ISO 527 part 1/2; Multi-purpose test specimentest speed 1 mm/min to ISO 3167
Flexural strength at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strength at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 23°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural strain at flexural strength at 80°C % ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 23°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Flexural modulus at 80°C MPa ISO 178 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eU 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at 23°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Charpy) at -30°C kJ/m2 ISO 179 1eA 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at 23°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Notched impact strength (Izod) at -30°C J/m ASTM D 256 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Puncture energy at 23°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Puncture energy at -30°C J/mm ISO 6603 part 2 60 x 60 x 2 mm
Maximum force N ISO 6603 part 2 60 x 60 x 2 mm
Thermal properties
Heat deflection temperature HDT/A (1.8 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
Heat deflection temperature HDT/C (8.0 MPa) °C ISO 75 part 1/2 80 x 10 x 4 mm from multi-pur-pose test specimen to ISO 3167
18
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
50 35 40 30 40 50 60 40 30
1.72 1.35 1.46 1.43 1.52 1.63 1.76 1.72 1.42
– – – – – – – – –
148 74 158 180 209 248 230 102 106
– – – – – – – – –
1 1.3 0.5 2.8 2.55 2.4 1.6 1.1 2.3
– – – – – – – – –
18,000 8,300 35,000 8,400 11,300 15,000 18,600 12,000 8,000
– – – – – – – – –
265 138 297 272 300 363 408 182 137
– – – – – – – – –
– – – – – – – – –
– – – – – – – – –
17,000 8,380 30,000 8,000 10,000 13,000 16,000 11,000 6,000
– – – – – – – – –
– – – – – – – – –
– – – – – – – – –
23 9 – 41 48 – 58 28 –
– – – – – – – – –
359 125 161 426 588 645 692 374 421
– – – – – – – – –
– – – – – – – – –
– – – – – – – – –
– – – – – – – – –
282 260 277 85 91 96 102 160 157
– – – – – – – – –
Celstran PPS Celstran TPU Celstran POM
PPS-GF PPS-AF PPS-CF TPU-GF TPU-GF TPU-GF TPU-GF POM-GF POM-AF50-01 35-01 40-01 30-01 40-01 50-01 60-01 40-01 30-01
19
3
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
4. Physical Properties
4.1 General information
Sections 4. “Physical Properties” and 5. “Environ-mental Effects” deal with the important propertiesthat are descriptive of Celstran and Compel, specifi-cally – where available – as a function of temperatureand time.
All properties are determined by standardized testmethods wherever possible. A survey of the physicalproperties is given in section 3. “Material Data”. Thevalues are also available as a data sheet.
With gentle processing a skeleton-like fibre structure is formed in Celstran and Compel mouldings. As a result they have properties characteristic of fibrecomposites. Compared with short-fibre-reinforced plastics there is a substantial improvement particu-larly in
- impact strength, notched impact strength, low-temperature impact strength,
- energy absorption capacity under impact stress,- rigidity and strength at elevated temperatures,- mechanical and thermal properties in continuous
service (creep, fatigue),- reduced warpage.
Of particular importance to designers is the verysharply reduced creep tendency brought about by thelong-fibre reinforcement. The orientation of the rein-forcing fibres frequently contributes to a reduction innotch sensitivity. A typical example is a screw injec-tion-moulded from Celstran: the fibre orientationgives it increased strength in the thread root betweenthe thread flights, fig. 4.1.
Generally speaking, long-fibre-reinforced plasticshave a high modulus of elasticity – typical values arebetween 10,000 and 20,000 MPa – with no change intheir good impact and notched impact strength, fig.4.2. Owing to their high rigidity and strength long-fibre-reinforced plastics are able to replace metals. Inspecific strength they far surpass metals, fig. 4.3.
Long-fibre materials
30,000
20,000
10,000
0100 200 300 400 500 J/m 700
Flex
ural
mod
ulus
E
Short-fibrematerials
Unreinforced termoplastics
Izod notched impact strength �K (ASTM D 256)
MPa
Fig. 4.2 · Comparison of the typical performanceranges of unreinforced, short-fibre-reinforced and
long-fibre-reinforced thermoplasticsSp
ecifi
c str
engt
h �
sp
0
5
10
15
20
25
30
16.5 17
5.1
9.8
5.9
12.7
23.5
17.2
CelstranPA66-GF40
CelstranPA66-GF50
CelstranPA66-CF40
PA66-GF60Celstran Steel* Zinc*
Aluminium* Magnesium*
km
� =
235
N/m
m2
� =
1.4
5 g/
cm3
� =
260
N/m
m2
� =
1.5
6 g/
cm3
� =
285
N/m
m2
� =
1.6
9 g/
cm3
� =
307
N/m
m2
� =
1.3
3 g/
cm3
� =
370
N/m
m2
� =
7.4
0 g/
cm3
� =
270
N/m
m2
� =
2.8
0 g/
cm3
� =
345
N/m
m2
� =
6.0
0 g/
cm3
� =
225
N/m
m2
� =
1.8
0 g/
cm3
*typical values
Fig. 4.3 · Specific strength of Celstran PA – reinforced with glass fibres or carbon fibres –
compared with metals
Fig. 4.1 · Long-fibre reinforcement in a threaded part reduces notch sensitivity in the thread root
20
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
A special advantage of Celstran PP is its low densitycompared e.g. to short-glass-fibre-reinforced PA, fig. 4.4.
Because of their low volume price resulting fromtheir low density, Celstran PP components can offersubstantial cost advantages over short-glass-fibre-reinforced PA66 and PA6, even if the fibre content inthe PP is higher than that in the PA, fig. 4.5.
Den
sity
�
1.0
1.2
1.4
1.6
1.8
2.0
2.2
2.4
g/cm3
2.8
Mag
nesi
um
Alu
min
ium
Cel
stran
PP-
GF3
0
1.12
Cel
stran
PP-
GF4
0
Cel
stran
PP-
GF5
0
PA6-
GV
30 s
hort
fibre
s
PA66
-GV
30 s
hort
fibre
s
PA66
-GV
40 s
hort
fibre
s
1.22
1.33 1.36 1.361.45
Fig. 4.4 · Density of some long- and short-fibre-reinforced plastics compared with light metals
5.00 DM / kg(price per kilo assumed as an example)
5.00
6.00
7.00
8.00
DM/l
Volu
me
pric
e
PA66
-GV
40 s
hort
fibre
sD
ensi
ty: 1
.45
g/cm
3
PA6-
GV
30 s
hort
fibre
sD
ensi
ty: 1
.36
g/cm
3
Cel
stran
PP-
GF5
0D
ensi
ty: 1
.33
g/cm
3
Cel
stran
PP-
GF4
0D
ensi
ty: 1
.22
g/cm
3
7.25
6.65
6.10
6.80
Fig. 4.5 · Comparison of the volume price of Celstran PP and short-fibre-reinforced PA66
that result from differences in density, assuming identical prices per kilo
4.2 Mechanical properties
4.2.1 Preliminary remarks
The properties of Celstran are determined by thestandard test methods used for the ®Campus materialsdata base. These properties make it easier for de-signers to make a preliminary selection of materials.
The physical property values given in section 3.“Material Data” may vary from those reached inmouldings owing to different production conditionsand processing parameters. In the case of Compel thevalues – also given in section 3. “Material Data” –were determined on specimens taken from compres-sion-moulded parts. These values are therefore notcomparable with those for Celstran. They reflect with reasonable accuracy the property values actuallyattained in mouldings.
In dimensioning components the long-term pro-perties and possibly the temperature-dependency ofthe properties as well as the values obtained undershort-term stress must be taken into account. It isthese long-term properties that are improved bylong-fibre reinforcement compared with the unrein-forced or short-fibre-reinforced matrix materials.
4.2.2 Short-term stress
Reinforcement with long fibres improves in particularstrength and modulus of elasticity at elevated temper-atures and/or under long-term stress compared withshort-fibre reinforcement. Long-fibre reinforcementalso gives better impact strength.
This is shown in fig. 4.6 for some important applica-tion properties of Celstran PP with chemically coup-led glass fibres. The flexural strength and flexuralmodulus values of a Celstran PP-GF40 are almostdoubled compared with a PP with 30% by weightshort glass fibres. The value for Charpy notchedimpact strength is nearly three times higher. A corre-sponding picture emerges for PA, i.e. with PA66 asmatrix material, fig. 4.7.
21
4
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
The combination of high flexural modulus and hightensile strength, fig. 4.8, opens up particularly in the case of Celstran PA fields of application in whichlight metal castings have been used in the past. In thissubstitution the benefits of the high rigidity of theCelstran PA grades, especially compared with short-fibre-reinforced PA, are a clear advantage, fig. 4.9.
Reinforcement with long glass fibres also increasesthe tensile modulus and tensile strength when POMis used as the matrix material, as shown by the stress-strain diagram for Celstran POM-GF40, fig. 4.10.
Tensile modulus[MPa]
Tensile strength[MPa]
Charpy notchedimpact strength
[kJ/m2]Flexural strength
[MPa]
Flexural modulus[MPa]
Fibre content[%]
40
9
806,200
100
5,500
9,500
195
9,100 115
20
30
PPshort-fibrecompound
PP- long-fibre pellets,
cemicallycoupled
Fig. 4.6 · Improvement in some typical mechanical properties of glass-fibre-reinforced PP on switching from commercial short-fibre products
to commercial long-fibre products
5,000
10,000
15,000
20,000
Flex
ural
mod
ulus
E
MPa
Tensile strength �
MPa150 200 250 300
Celstran PA66
25%
30%
40%
40% 50%
60%
PA66 short fibres
Fig. 4.8 · Tensile strength and flexural modulus of some Celstran PA66 grades compared
with short-glass-fibre-reinforced PA66
conditioned
Stre
ss �
Strain ε
Celstran PA66-GF50
Celstran PA66-GF40
PA66-GV33short fibres
0 1 2 3 40.5 1.5 2.5 %0
50
100
150
200MPa
Fig. 4.9 · Stress-strain curves for Celstran PA grades and short-glass-fibre-reinforced PA66
Strain ε
Stre
ss �
00
40
80
MPa
120
0.4 0.8 1.2%
Fig. 4.10 · Stress-strain curve for Celstran POM-GF40
10,700
13,000
35
50
32
26017,000
405
15,000
210
305 13
Tensile modulus[MPa]
Tensile strength[MPa]
Charpy notchedimpact strength
[kJ/m2]Flexural strength
[MPa]
Flexural modulus[MPa]
Fibre content[%]
PAshort-fibrecompound
PA- long-fibre pellets,
freshlymoulded
Fig. 4.7 · Improvement in some typical mechanical properties of glass-fibre-reinforced PA66 on switching from commercial short-fibre
products to commercial long-fibre products
22
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
4.2.3 Creep properties
Designers have to know the creep properties of components subject to constant mechanical stress.Depending on the test conditions, these properties indicate how
- strain at constant stress increases with time(creep test to ISO 899 part 1)
- stress at constant strain decreases with time(stress relaxation test to DIN 53441).
The increase in strain under constant load, known as flow, shown in stress-strain curves is considerablyless in the case of Celstran PP than in the case of acomparable short-fibre-reinforced PP, fig. 4.11. Asthe diagram shows, the creep tendency is even less than that of short-fibre-reinforced PA66.
0.10
1
1 10 100 1,000
2
3
4
Stra
in �
Time th
PA66-GV30short fibres
PP-GV30short fibres
Celstran PP-GF50
%
CelstranPP-GF40
Fig. 4.11 · Creep curves for two Celstran PP grades(PP-GF40 and PP-GF50) compared with short-glass-fibre-reinforced PP (PP-GF30) and short-glass-fibre-
reinforced PA66 (tensile stress: 35 MPa)
In similar fashion to when PP is used as matrix material, the long glass fibres in PA66 reduce thecreep tendency substantially. This is evident particu-larly at high load with a tensile stress of 90 MPa, fig. 4.12.
Details of the creep properties of Celstran PA66-GF40 – measured in accordance with ISO 899part 1 – are given in figs. 4.13 and figs. 4.14. Thecorresponding details for Celstran PA66-GF60 are given in figs. 4.15 and figs. 4.16.
For stress at high temperature and very high load(120°C and 120 MPa) fig. 4.17 shows the creep properties of Celstran PP-GF40 characterized by the flexural creep modulus compared with a short-fibre-reinforced PP. In this accelerated test the long-fibre-reinforced material does not fail even after atime under load of 100 hours.
Celstran PA66-GF40
PA66-GV40short fibres
Time t
Stra
in �
0.5
1
1 10 100 1,000
2
%
0.1
1.5
2.5
h
Fig. 4.12 · Decrease in creep tendency of PA66 when reinforced with long fibres: comparison of
a short-glass-fibre-reinforced material and CelstranPA66-GF40 (tensile stress: 90 MPa) Time t
Stra
in �
0.03
0.1
0.3
1
3
%
Equivalent stress 10 MPa
30
5070
90100
100 10-1 101 102 103h
Fig. 4.13a · Characteristic values for the creep behaviour of Celstran PA66-GF40:
creep curves for various stress values
100 10-1 101 102 103
Equi
vale
nt s
tress
�0
300
100
30
10
MPa
strain 0.2%
0.4%
0.6%
0.8%1.0%
hTime t
Fig. 4.13b · Characteristic values for the creep behaviour of Celstran PA66-GF40: creep curves
for various strain values
23
4
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
00
25
50
75
MPa
100
0.4 0.8 1.2 % 1.6Strain �
Equi
vale
nt s
tress
�0
Time under stress T 0.1h1
10 102
103
104 (extrapolated)
0.4
10
0.50.6
0.3
0.2
Strain 0.1%
300
100
30
100 10-1 102 103hTime t 101
Equi
vale
nt s
tress
�0
MPa
15,000
10,000
5,000
0
Cre
ep m
odul
us E
c
MPa 2550
75
Equivalent stress 100 MPa
100 10-1 101 102 103hTime t
102
103
104
100
75
50
25
00 0.25 0.50 0.75 % 1
0.1h
1
10
(extrapolated)
Strain �
Equi
vale
nt s
tress
�0
MPaTime under stress T
0.3
0.03
1
0.1
100
90
70
50
30
Stra
in �
%
Equivalent stress MPa
100 10-1 101 102 103hTime t
Cre
ep m
odul
us E
c
25,000
20,000
15,000
75
50
25
Equivalent stress MPa
100 10-1 101 102 103hTime t
MPa
Fig. 4.14a · Characteristic values for the creep behaviour of Celstran PA66-GF40:
stress-strain curves for various times under stress
Fig. 4.14b · Characteristic values for the creep behaviour of Celstran PA66-GF40: creep modulus
as a function of time for various stress values
Fig. 4.15a · Characteristic values for the creep behaviour of Celstran PA66-GF60: creep curves
for various stress values
Fig. 4.15b · Characteristic values for the creep behaviour of Celstran PA66-GF60: creep curves
for various strain values
Fig. 4.16a · Characteristic values for the creep behaviour of Celstran PA66-GF60: stress-strain
curves for various times under stress
Fig. 4.16b · Characteristic values for the creep behaviour of Celstran PA66-GF60: creep modulus
as a function of time for various stress values
24
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
0.10
1,000
2,000
3,000
4,000
1 10 h 100
Celstran PP-GF40
failure
Time under stress t
Cre
ep m
odul
us E
c
MPa
PP-GV40short fibres
Fig. 4.17 · Flexural creep modulus of Celstran PP-GF40 as a function of time comparedwith a PP with 40% by weight short glass fibers [6]
(flexural stress: 120 MPa, temperature: 120°C)
15,000
10,000
5,000
00 10 20 30 40 50 70
Charpy impact strength �s
Flex
ural
mod
ulus
E
35%
25%
25%
35%
40%
30%
kJ/m2
PA-GVshort fibresconditioned
PP-GVshort fibres
20%
PA-GVshort fibresfreshly moulded
50% CelstranPP-GF
MPa
Fig. 4.19 · Flexural modulus as a function of Charpy impact strength of Celstran PP compared
with short-fibre-reinforced plastics
3,000
4,000
2,000
1,000
500
15 2010Deflection s
N
mm
Forc
e F
PP-GV40short fibres
CelstranPP-GF40
Fig. 4.20 · Force-deflection curve in the instrumented puncture test on Celstran PP-GF40 and a polypropylene with 40% short glass fibres
long fibreslong fibreslong fibres
short fibresshort fibres
Temperature [°C]
Izod
not
ched
impa
ct s
treng
th �
K*
-40 -30 -20 -10 0 20 °C0
200
400
600
800
J/m
Celstran PP-GF30
PA66-GV30 short fibres
PP-GV30 short fibres
*according to ASTM D 256
Celstran PP-GF50
Celstran PP-GF40
Fig. 4.18 · Improvement in low-temperature impactstrength by long-fibre reinforcement: comparison of
various Celstran PP grades with short-glass-fibre-rein-forced PP and with short-glass-fibre-reinforced PA66
Direct information on the behaviour under impactstress is provided by the multi-axial stress in thepenetration test. The results are shown in fig. 4.20 forCelstran PP and fig. 4.21 for Celstran PA. In bothcases the long-fibre reinforcement substantiallyincreases the maximum force and the fracture energy(this corresponds to the area beneath the curve).
Compel components have even better impact strengththan comparable Celstran components. The increasewith PP as matrix material is about 40% for theimpact-resistant formulation (Compel PP-GF30-05P25).
4.2.4 Toughness
Toughness is crucial to the behaviour of a componentunder impact stress. As already shown in figs. 4.6 forCelstran PP and 4.7 for Celstran PA, long-fibre rein-forcement brings an above-average increase in impactstrength.
This applies not only at room temperature but also tolow-temperature impact strength, fig. 4.18. With thecombination of high flexural modulus and very goodimpact strength, fig. 4.19, the long-fibre-reinforcedCelstran can be used in those cases in which thiscombination of properties is not adequate in short-fibre-reinforced plastics.
25
4
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
5,000
4,000
3,000
2,000
1,000
00 2 4 6 8mm
N
PA66-GV40short fibres
CelstranPA66-GF40
Deflection s
Forc
e F
Fig. 4.21 · Force-deflection curve in the instrumentedpuncture test on Celstran PA66-GF40 and a
polyamide with 40% by weight short glass fibres
Fig. 4.22 · Results of the tensile fatigue test on glass-fibre-reinforced polypropylene at elevated
temperature (70°C)
4.2.5 Fatigue
Components that are subject to fluctuating stressmust be dimensioned by means of the fatigue strength.
The long-fibre reinforcement substantially increases the fatigue strength at room temperature and espe-cially at elevated temperature and high load comparedwith short-fibre reinforcement, fig. 4.22.
The flexural fatigue strength*) of Celstran PP-GF40 compared with a short-fibre-reinforced PP is shown in fig. 4.23.
4.2.6 Surface properties
Celstran mouldings generally have a good surfacebecause of the good flowability of the melt. For partswith visible surfaces the following grades are highlysuitable:
- Celstran PP grades with modification 04(increased flowability)
- Celstran PA grades with modification 01(high gloss).
In each case graining of visible surfaces isrecommended.
Sliding properties: As with unreinforced plastics, an addition of PTFE improves the sliding properties of Celstran. A Celstran PA-GF50 modified withPTFE to suppress the stick-slip effect is obtainablefrom Lehmann & Voss & Co., Hamburg, Germany.
Wear: Like the sliding properties, wear is a characte-ristic of the system. Abrasion is dependent on varia-bles such as sliding partner, surface pressure, slidingspeed and lubrication. Under comparable conditionsCelstran PP and Celstran PA generally display lessabrasion than corresponding short-fibre-reinforcedmaterials, fig. 4.24: abrasion against steel of long- and short-fibre-reinforced PA66 (40% by weightglass fibres).
Stre
ss a
mpl
itude
�
A
70
50
40
30
20103
Number of cycles n
PP-GV30short glass fibres
104 105 106 107 108
MPa
Celstran PP-GF40
Fig. 4.23 · Flexural fatigue strength of Celstran PP-GF40 compared with PP reinforced
with 30% by weight short glass fibres
Stress amplitude Number of cycles until failure of
Celstran PP-GF40 PP-GV40MPa long fibres short fibres
80 14 1
60 300 66
50 871 182
*) Fatigue strength: Stress amplitude determined in a fatigue testthat a specimen withstands for a specific number of load cycleswithout fracture.
26
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
Rela
tive
abra
sion
8
4
6
2
0
PA66
-GV
40(4
0% b
y w
eigh
t sho
rt fib
res)
Test material
Taber abrasion method
Cel
stran
PA
66-G
F40
(40%
by
wei
ght
long
fibr
es)
Fig. 4.24 · Abrasion against steel of long- and short-fibre-reinforced PA66
(40% by weight glass fibres)
4.3 Thermal properties
4.3.1 Coefficient of expansion
Fibre reinforcement substantially reduces the coeffi-cient of linear thermal expansion of plastics. Becauseof the skeleton structure the differences in flow direc-tion and perpendicular to it are less than for compa-rable short-fibre-reinforced materials.
The coefficient of expansion of Celstran reaches values of 10 to 20 · 10–6 · °C–1 in the temperature range–30 to +30°C for the different test specimen geo-metries, fig. 4.25. It is thus in the same range as steel(12.1 · 10–6 · °C–1) and aluminium (22.5 · 10–6 · °C–1).
4.3.2 Specific heat, enthalpy
For designing the processing machines and mouldsand for dimensioning mouldings it is necessary toknow the amount of heat that has to be supplied formelting the long-fibre-reinforced thermoplastics andthen removed from the mould by cooling. Fig. 4.26shows by way of example the specific enthalpy curveof Celstran PP with 40% by weight long glass fibresas a function of temperature. The amount of heat tobe removed from the mould can be calculated fromthe melt temperature and the demoulding temperatu-re for Celstran PP with the values given in fig. 4.27 in accordance with the procedure in fig. 4.28.
00
100
200
300
400
J/g
600
50 100 150 200 250 °C 350Temperature �
Spec
ific
enth
alpy
Fig. 4.26 · Specific enthalpy (based on 20°C) as a function of temperature for Celstran PP-GF40
Fig. 4.25 · Coefficients of thermal expansion (range: –30 to +30°C)
of some frequently used Celstran grades
Material Coefficient of expansion (-30 to +30°C)
in perpendicularflow direction to flow direction
Celstran 10-6 · °C-1 10-6 · °C-1
PA66 unreinforced 90 not measurable
PA66-GF40 19 not measurablePA66-GF50 17 not measurablePA66-GF60 15 not measurable
PA66-CF40 13 not measurable
PP unreinforced 83 not measurable
PP-GF30 16 36PP-GF40 15 34PP-GF50 13 17
PET-GF40 16 72
PBT-GF40 19 75
PC/ABS-GF40 18 70
PPS-GF50 12 39
TPU-GF40 13 52TPU-GF50 10 50
TPU-CF40 18 64
Blends
PA66-SF6 66 74
ABS-SF6 64 96
PC-SF10 43 –
27
4
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
4.3.3 Thermal conductivity
Generally speaking, the reinforcing fibres have higherthermal conductivity than the matrix material.Therefore the thermal conductivity of fibre-reinfor-ced plastics rises slightly with the fibre content. Thethermal conductivity of Celstran PP-GF50 black (at30°C) is λ= 0.28 ± 0.01 W/(m·K).
4.4 Electrical properties
Reinforcement with electrically non-conductive glassfibres or aramid fibres has no appreciable influence on the electrical properties of the individual matrixmaterial. In particular the very good electrical insula-ting properties and good dielectric strength of theplastics remain virtually unchanged.
Of the Celstran grades with carbon fibre reinforce-ment PA66-CF40 has good conductivity and evensome shielding effect against electromagnetic radiati-on. Because of these properties this material is usede.g. for the housings of laptops. By adding a smallamount of stainless steel filaments the shielding effectand surface conductivity of plastics can be increasedspecifically. The Celstran SF masterbatches, which aredescribed in more detail in the offprint B182 d + e“Stainless steel fiber filled plastics – shielding compo-nents” (delivery upon request), were developed spe-cially to meet these requirements.
Fig. 4.28 · Procedure for calculating the amount of heat to be removed on solidification
Celstran PP-GF40:Cooling from 250°C to 72 °C
Enthalpy at 250°C 470 J/g- Enthalpy at 72°C 77 J/g
= heat to be removed 393 J/g
Fig. 4.27 Values for specific enthalpy of polypropylene, glass and Celstran PP grades, based on 20°C
Temperature Specific enthalpy in J/g, based on 20°C, of
°C PP Glass Celstran PP-GF30 Celstran PP-GF40 Celstran PP-GF50
20 0 0 0 0 0
50 55 24 46 43 40
72 100 42 82 77 71
100 160 64 131 122 112
115 200 76 163 150 138
150 310 104 248 228 207
170 400 120 316 288 260
172 445 122 348 316 283
200 525 144 411 373 334
250 660 184 517 470 422
300 795 224 624 567 510
28
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
4.5 Optical properties
Fibre-reinforced thermoplastics are not transparent and are translucent only if the wall thickness is low.
4.6 Acoustic properties
From the acoustic point of view components madefrom long-glass-fibre-reinforced Celstran PP offerthe following advantages:
- they have considerably better sound-deadeningproperties than components made from short-fibre-reinforced PA or metal
- noise emission is lower because of the highersound-deadening effect
- owing to their high rigidity the natural frequency ishigher, given otherwise unchanged conditions, andso additional ribs to increase the natural frequencyare not necessary
- they have lower oscillation amplitudes – with thesame design rigidity
- large-volume hollow components also attain highacoustic damping
- they permit a reduction in weight because of theiracoustic passivity.
The good acoustic damping is shown by oscillationmeasurements on cable trays for the electronic enginecontrol system of cars: because of its lower weight and higher rigidity the cable tray made from CelstranPP-GF40 has a higher natural frequency at a muchlower amplitude than a cable tray made from PA6with 30% by weight short glass fibres, fig. 4.29.
Because of their good acoustic damping propertiescomponents made from Celstran have good sound-deadening properties, fig. 4.30.
Fig. 4.29 · Frequency spectra on excitation with a rectangular impulse, measured on cable trays
made from Celstran PP-GF40
0.6
dB
0.4
0.3
0.2
0.1
0.0
0 200 400 600 Hz 1,000
Frequency
Am
plitu
de
PA6-GV30short glassfibres Celstran PP-GF40
292 Hz
306 Hz
0 s0
20
40
60
%
100
0.05 0.10 0.15 0.20
Time t
Rela
tive
ampl
itude
PA6-GV30 short fibres
Celstran PP-GF40
Fig. 4.30 · Decay curve on excitation with a rectangular impulse, measured on cable trays made from Celstran PP-GF40 and from a PA6
with 30% by weight short glass fibres
29
4
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
30
Temperature �
Shea
r m
odul
us G
16,000
8,000
4,000
00 100 °C 25015050-50
MPa
Celstran PA66-GF60-02Celstran PA66-GF50-02
Celstran PA66-GF40-02
Fig. 5.2 · Shear modulus of various Celstran PA grades as a function of temperature
5. Environmental Effects
5.1 Thermal properties
5.1.1 Heat deflection temperature
Because of the long-fibre reinforcement the heatdeflection temperature of all Celstran grades is signi-ficantly higher than that of the corresponding short-fibre-reinforced matrix materials.
The long-fibre reinforcement of Celstran PP-GF40accounts for the shear modulus up to a temperatureof 130°C being higher than that of short-glass-fibre-reinforced PA6 and PA66, fig. 5.1. Shear modulus of Celstran PA is plotted against temperature in fig.5.2. The long-fibre reinforcement furthermore sig-nificantly reduces the creep tendency compared withthat of corresponding short-fibre-reinforced plastics.This is shown by stress-strain curves of PP measuredat 120°C, fig. 5.3.
5.1.2 Heat ageing
The heat ageing of plastics is not a pure material pro-perty but is also dependent on environmental circum-stances, the loading condition and the natural colour of the material.
The base material used for Celstran PP is stabilizedeffectively against thermo-oxidative degradation andtherefore displays good ageing properties.
Because of their good heat ageing properties lightlystressed Celstran PP components are suitable for continuous service temperatures up to 130°C. Undershort-term stress – up to about 1,000 hours – tempe-ratures up to 150°C can be tolerated (medium: air).
In the flexural test based on ISO 178 the flexuralmodulus and flexural strength even rise slightly afterheat ageing, whereas the strain, normally highly sensitive to ageing, falls only slightly, fig. 5.4.
The base material of the heat-stabilized Celstran PA(modification -02) is stabilized against thermo-oxi-dative and hydrolytic degradation. Componentsmade from heat-stabilized Celstran PA are suitableunder low loading for continuous service tempera-tures up to 150°C and for short periods – up to about 1,000 hours – for temperatures of 170 to 200°C
1
0.5
%
0 500 1,000 h 1,500Time t
Stra
in
�
0
Celstran PP-GF40
PP-GV40 short fibres
Fig. 5.3 · Creep curves for Celstran PP-GF40 compared with a PP with 40% by weight
short glass fibres
5,000
2,000
1,000
500
200-50 0 50 °C 150
Temperature �
Shea
r m
odul
us G
MPa
Celstran PP-GF40
PA66-GV30 cond.short fibres
PA6-GV30 cond.short fibres
Fig. 5.1 · Shear modulus of Celstran PP-GF40 as a function of temperature compared with
conditioned PA6 and PA66, each with 30% by weight short glass fibres
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
(medium: air). At a temperature of 150°C even aftermore than 500 hours heat ageing Celstran PA66-GF40-02 has a flexural modulus of over 10,000 MPa, fig. 5.5, while Celstran PA66-GF50-02 has a flexuralmodulus of over 12,000 MPa, fig. 5.6.
Because of their good heat ageing properties theCelstran PA grades frequently replace light metals in the manufacture of complex castings. They usuallypermit considerably higher functional integration.
5.2 Flammability
The behaviour of numerous Celstran grades in theevent of fire has been tested and classified to UL 94.Fig. 5.7 shows an extract from these ratings, whichare constantly being updated.
Celstran PP-GF30 test specimens have withstoodexposure to edge and surface flame application inaccordance with DIN 4102 B2.
31
Flex
ural
mod
ulus
EFl
exur
al s
train
at b
reak
�Fl
exur
alstr
engt
h �
B
2.30
%
2.10
2.00
1.90
190
170
160
15010 100 h 1,000
Heat ageing time t
MPa
11,500
10,500
10,000
9,500
MPa 150°C
130°C
130°C
150°C
150°C
130°C
Fig. 5.4 · Heat ageing of Celstran PP-GF40-04-P10 black
Flex
ural
mod
ulus
EB
Stra
in �
Flex
ural
stren
gth
�B
2.2
%
2.0
1.8
330
300
270freshly
moulded500 h 1,000
Heat ageing time t
MPa
12,000
10,000
8,000
MPa
200100
Flex
ural
mod
ulus
EB
Fig. 5.5 · Heat ageing of Celstran PA-GF40-02-P10 black
Flex
ural
mod
ulus
EB
Stra
in �
Flex
ural
stren
gth
�B
2.0
%
1.8
1.6
450
350
250freshly
moulded500 h 1,000
Heat ageing time t
MPa
14,000
12,000
10,000
MPa
200100
Fig. 5.6 · Heat ageing of Celstran PA-GF50-02-P10 black
Fig. 5.7 · UL rating of flammability and relative temperature index (RTI) of some Celstran PP
and PA grades
Material Colour Thick- Flamm. Temperature indexness class elec. mechan.[mm] UL 94 with without
impact impact
PolypropylenePP-GF30 natural 1.57 HB 65 65 65PP-GF40 natural 1.57 HB 65 65 65PP-GF50 natural 1.57 HB 65 65 65
PolyamidePA66-GF40 natural 1.57 HB 65 65 65
black 3.17 HB 65 65 65PA66-GF50 natural 1.57 HB 65 65 65
black 3.17 HB 65 65 65PA66-GF50HG all 1.5 HB 65 65 65
3.0 HB 65 65 65PA66-GF60 natural 1.57 HB 65 65 65
black 3.17 HB 65 65 65PA6-CF35-10 black 1.2 V-0
5
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
In the flammability test to FMVSS 302 frequentlyused in the vehicle industry the following values wererecorded on 1-mm thick test specimens:
- Celstran PP-GF40 burning rate 1.61 inch/min,- Celstran PP-GF50 burning rate 1.63 inch/min.
Both materials thus qualify for a standard burningrate of less than 4 inch/min. Their burning rate isbelow the value of 2.37 inch/min measured on short-fibre-reinforced PP-GV30.
5.3 Chemical resistance
The chemical resistance is influenced essentially bythe base material. Celstran PP and Celstran PA areresistant to glycol-water mixtures (engine cooling incars) up to 135°C. The changes with time of themechanical properties at 132°C are shown in fig. 5.8,fig. 5.9, fig. 5.10 and fig. 5.11.
5.4 Weathering and UV resistance
Celstran PP and Celstran PA can be supplied onrequest with highly effective light stabilization.
32
Flex
ural
stre
ngth
�B
750 h 1,000Immersion time t
400
200
100
00
MPa
250 500
Celstran PA66-GF40-02P10 black
Celstran PA66-GF30-02P10 black
Celstran PP-GF50-04P10 black
Fig. 5.8 · Effect of heat ageing at 132°C in a glycol-water mixture on the flexural strength of
various Celstran grades
Cha
rpy
impa
ct s
treng
th a
750 h 1,000Immersion time t
100
60
40
00
kJ/m2
250 500
Celstran PA66-GF40-02P10 black
Celstran PA66-GF30-02P10 black
Celstran PP-GF50-04P10 black20
Fig. 5.9 · Effect of heat ageing at 132°C in a glycol-water mixture on the Charpy impact strength
of various Celstran grades
Tens
ile s
treng
th �
Z
750 h 1,000Immersion time t
250
150
100
00
MPa
250 500
Celstran PA66-GF40-02P10 black
Celstran PA66-GF30-02P10 black
Celstran PP-GF50-04P10 black50
Fig. 5.10 · Effect of heat ageing at 132°C in a glycol-water mixture on the tensile strength of
various Celstran gradesTe
nsile
stra
in a
t bre
ak �
750 h 1,000Immersion time t
3
2
1
00
%
250 500
Celstran PA66-GF40-02P10 black
Celstran PA66-GF30-02P10 black
Celstran PP-GF50-04P10 black
0.5
1.5
Fig. 5.11 · Effect of heat ageing at 132°C in a glycol-water mixture on the elongation at break
of various Celstran grades
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
6. Processing
Celstran is intended for injection moulding, blowmoulding and extrusion. Compel is suitable for plasticizing/compression moulding. In processing allCelstran and Compel grades care should be taken toensure that fibre breakage is kept to a minimum. Thelonger the glass fibres in the component, the betterare its mechanical properties.
6.1 Preparation
The pellets should be stored in a dry place in closedcontainers until they are processed so as to preventcontamination and moisture absorption (including condensation).
Celstran PP and Compel PP: drying is not normallyrequired before processing. Should the material havebecome damp owing to incorrect storage, it must bedried for 2 hours at 80°C.
Celstran PA: drying in a dehumidifying dryer for 4 hours at 80°C is recommended in principle beforeprocessing.
Other Celstran grades: drying in a dehumidifyingdryer is in principle recommended before processing.The drying conditions are given in the product datasheet – see fig. 6.5.
33
6.2 Injection moulding of Celstranincluding mould making
Celstran can be processed by the various injectionmoulding methods commonly used for thermopla-stics. For the gentlest possible melting it is generallyrecommended that screw speed, injection speed andback pressure should be kept as low as possible.
6.2.1 Machine requirements
All Celstran grades can be processed on commercialinjection moulding machines. For optimum care ofthe reinforcing fibres and to prevent feed problemsbecause of the relatively long pellets, fairly large pla-sticizing machines should be used, preferably with ascrew diameter of more than 40 mm.
Pellets 7 mm long are available for processing glass-fibre-reinforced Celstran PA66 grades on smallermachines. Three-zone screws are recommended, fig. 6.1, if possible with a deep-flighted feed zone,low compression ratio and a three-piece annular non-return valve of large cross-section to ensure smootheven flow, fig. 6.2. Plasticizing units with mixingzones are in principle not suitable.
Fig. 6.1 · Metering Screw for Celstran Materials Fig. 6.2 · Three Piece Screw Tip Ring Valve
total length
generously dimensioned slotsfor gentle melt throughput
precision-ground mating surfacesfor good seal
highly polished
effective screw length
outside diameter
flight depth,metering zone
non-return valve
screw tip
met
erin
g zo
ne
com
pres
sion
zone
feed
zon
e
shaf
t len
gth
flight depth,feed zone
5
6
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
6.2.2 Processing conditions
Celstran can be injection-moulded without anyproblems. Machine settings that result in optimumfinished parts are dependent on the moulded partgeometry, the injection mould and the injectionmoulding machine used. Settings that have provedsuccessful are given in
- fig. 6.4 for Celstran PP and Celstran PA,- fig. 6.5 for other Celstran grades.
Plasticizing and cylinder temperatures
Gentle plasticizing is necessary to keep fibre lengthreduction during melting to a minimum. The requi-red melt temperature is achieved firstly by cylinderheating (heat supply from outside by heat conduc-tion) and secondly by friction (heat supply throughinternal and external friction, produced by back pressure and screw speed).
The melt shear occurring on melting may shorten thelong reinforcing fibres. It is therefore particularlyimportant to maintain very low back pressure oreven to plasticize without back pressure, but at thesame time to ensure uniform metering and adequatemelt homogeneity. It is recommended that the screwspeed should be as low as possible so that about 90%of the cooling time can be utilized for metering. Inorder for a maximum amount of heat to be suppliedvia the cylinder heating, the pellets should meltrapidly in the feed zone. For this material, therefore,a somewhat higher temperature profile should bechosen than for processing corresponding short-fibrecompounds.
Mould wall temperatures
The recommended mould wall temperatures are governed by the matrix material. Details are given infigs. 6.4 and 6.5. For Celstran PP mould wall tempe-ratures of 40 to 50°C have proved successful.Mouldings with a very good surface are obtained ifthe mould wall temperature is raised to 70°C. Themould wall temperatures for Celstran PA are nor-mally 90°C.
Since all Celstran grades contain reinforcing fibres, itis necessary for the plasticizing unit to be wear-resi-stant. Depending on the matrix material, additionalcorrosion protection may be necessary, e.g. for PA66or PPS.
Details of recommended machine equipment aregiven in fig. 6.3. Pneumatic conveying equipment hasproved successful for automatic material supply. Thediameter of the conveying lines should be at least 40 mm. Low air speeds (up to about 16 m/s) shouldpreferably be used. Suction tubes cut at an angle haveproved successful for feeding the product.
Gravimetric metering equipment is recommended forproducing blends with a fairly low fibre content.
The conveying and metering equipment used in pro-ducing conductive blends of Celstran with stainlesssteel filaments must not have any magnetic compo-nents. These blends can also be processed on machi-nes with smaller screws (diameter 20 mm and above)owing to the good stability of the stainless steel fila-ments.
34
Fig. 6.3 · Recommended equipment and parameters for injection moulding machines for
processing Celstran PP and Celstran PA
Celstran PP Celstran PA
Machine size preferably fairly large machines
Screw standard 3-zone screw,screw diameter preferably ≥ 40mm
Non-return valve streamlined non-return valve for good flow,with large cross-section
L/D 18 : 1 to 22 : 1 18 : 1 to 22 : 1
Compression ratio 1 : 1.8 to 1 : 2.5 1 : 1.8 to 1 : 2.5
Functional feed 50 to 60%zone ratios compression 20 to 30%
metering 20%
Flight depth feed zone preferably ≥ 4.5mm
Steel quality wear-resistant wear-resistantsteels and corrosion-HRC ≥ 56 resistant steels
HRC ≥ 56
Shot weight 30 to 60% of machine capacity
Nozzle open, diameter ≥ 4mm, preferably ≥ 6mm,own temperature control for the nozzle
Gating if possible central sprue gate, diameter ≥ 4 mm, preferably ≥ 6mm, all flow channels streamlinedfor good flow, gate diameter ≥ 3mm, if possible
no pin or film gates
Predrying 4h at 80°Cdehumidifying dryer
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
35
Celstran PP Celstran PAheat stabilized = 02 high-gloss = 01
PP-GF30 PP-GF40 PP-GF50 PA66-GF40 PA66-GF50 PA66-GF60 PA66-GF40 PA66-GF50 PA66-GF60
Temperature [°C] 230 to 270 250 to 290 250 to 290 275 to 310 280 to 315 285 to 320 270 to 305 270 to 305 275 to 310cylinder
Temperature [°C] 240 to 270 260 to 290 280 to 290 305 to 315 310 to 320 315 to 325 290 to 305 295 to 305 295 to 310nozzle and melt
Temperature [°C] 30 to 70 40 to 70 40 to 70 80 to 120 80 to 120 80 to 120 70 to 110 70 to 110 70 to 110mould pref. 90 pref. 90 pref. 90 pref. 90 pref. 90 pref. 90
Injection [mm/sec] 40 to 60 40 to 60 40 to 60 40 to 75 40 to 75 40 to 75speed
Screw speed [min-1] 40 to 60 40 to 60 40 to 60 40 to 60 40 to 60 40 to 60
Holding pressure [bar] 400 to 800 400 to 800 400 to 800 500 to 800 500 to 800 500 to 800
Injection pressure [bar] 600 to 1200 600 to 1200 600 to 1200 1200 to 1500 1200 to 1500 1200 to 1500
Back pressure as low as possible as low as possible
Fig. 6.5 · Drying and processing conditions for other Celstran grades
Drying Processing Processing Injection Back Screwtemperatures [±10°C] temperatures [±10°C] speed pressure speed
Time Temp Cylinder temperatures Nozzle Melt Mould Commentsat at
Product [h] [°C] hopper centre nozzle [bar] [min-1]
Polybutylene terephthalatePBT-GF40-01P10 4 120 255 260 265 260 265 90 medium 0 to 3 30 to 50 Predry to 0.015%PBT-GF50-01P10 4 120 260 265 270 265 270 90 medium 0 to 3 30 to 50 moisture content
Polycarbonate blendPC/ABS-GF25-02P10 4 90 265 270 275 275 275 80 medium 0 to 3 30 to 50PC/ABS-GF40-02P10 4 90 270 275 280 280 280 80 medium 0 to 3 30 to 50
PolyethylenePE-HD-GF60-03P10 2 90 230 240 250 240 250 70 medium 0 to 3 40 to 60
Polyethylene terephthalatePET-GF40-01P10 4 150 265 270 275 270 275 150 medium 0 to 3 30 to 50 Predry to 0.015%PET-GF50-01P10 4 150 270 275 285 280 285 150 medium 0 to 3 30 to 50 moisture content
Polyphenylene sulphidePPS-GF50-01P10 4 130 305 315 320 310 320 150 medium 0 to 2 30 to 50 Predry to 0.02%
moisture content
Polyoxymethylene (Polyacetal)POM-GF40-01P10 3 80 195 200 205 205 205 80 medium 0 to 3 30 to 50 Melt < 230°C
Thermoplastic polyurethaneTPU-GF30-01P10 4 80 240 245 250 245 250 70 medium 0 to 3 30 to 50 Predry to 0.02%TPU-GF40-01P10 4 80 245 250 255 250 255 70 medium 0 to 3 30 to 50 moisture contentTPU-GF50-01P10 4 80 250 255 260 255 260 70 medium 0 to 3 30 to 50 Melt < 275°CTPU-GF60-01P10 4 80 255 260 265 260 265 70 medium 0 to 3 30 to 50
With aramid fibresPA66-AF35-02P10 4 80 295 310 315 310 315 90 medium 0 to 3 30 to 50POM-AF30-01P06 3 80 200 205 210 210 210 70 medium 0 to 3 30 to 50PPS-AF35-01P06 4 130 315 320 320 320 320 150 medium 0 to 3 30 to 50
With carbon fibresPA66-CF40-01P10 4 80 300 305 310 310 310 90 medium 0 to 3 30 to 50PPS-CF40-01P10 4 130 305 310 315 315 315 150 medium 0 to 3 30 to 50TPU-CF40-01P10 4 80 245 250 255 255 255 70 medium 0 to 3 30 to 50
Fig. 6.4 · Processing conditions for Celstran PP and PA
6
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
Injection and holding pressure
High shear can also occur in the melt in the injectionoperation and shorten the fibres. Therefore low injec-tion speeds are recommended. Injection and holdingpressure should be adapted to the moulded part geo-metry. A holding pressure of 60 to 100% of the injec-tion pressure is recommended. To ensure as constanta moulded part quality as possible, an adequate hol-ding pressure time must be ensured. This is achievedwhen the moulded part weight remains constantdespite a lengthy holding pressure time with a con-stant total cycle time.
Regrind addition
When Celstran is processed, it is possible to addcoarsely ground production waste to virgin materialof the same grade. Additions of up to 10% have vir-tually no adverse effect on moulded part properties[3], fig. 6.6.
6.2.3 Flow properties and flow path lengths
In the spiral flow test under simulated service con-ditions the Celstran PP grades reach flow path lengths up to 550 mm for 2 mm wall thickness at aninjection pressure of 1,000 bar and a melt temperatureof 245°C, fig. 6.7. Raising the melt temperature by 45 K to 290°C increases the flow path length byabout 15%, fig. 6.8. Thus, despite reinforcement withlong glass fibres the flowability of Celstran PP is better than that of standard PP compounds with acomparable short glass fibre content, fig. 6.9.
Similarly, the Celstran PA grades too have betterflowability than corresponding short-fibre com-pounds. Even the heat-stabilized grades reach flowpath lengths up to 300 mm in the spiral flow test atan injection pressure of 1,000 bar and a melt tempera-ture of 305°C, fig. 6.10. Raising the melt temperatureby only 15 K to 320°C increases the flow path lengthby over 20%, fig. 6.11.
6.2.4 Shrinkage
Shrinkage has a major influence on the dimensional stability and warpage of a moulding. It is governed not only by the fibre content but also to a consider-able extent by the fibre orientation and the processingconditions, and so shrinkage data can be no morethan guide values.
Despite reinforcement with long glass fibres the anisotropy of shrinkage, i.e. the ratio of longitudinalto transverse shrinkage, is fairly low and generallymore favourable than that of short-fibre-reinforcedplastics. The average shrinkage measured on test barsis 0.25% in flow direction and 0.3% in transversedirection. Owing to the low anisotropy of shrinkagethe warpage tendency of Celstran components issimilarly low.
Additional information on the dimensional accuracyof Celstran components can be derived from the ratio of the flexural modulus in flow direction to thatin transverse direction. This anisotropy is muchlower in Celstran PP components than in identicalcomponents made from a corresponding short-fibre compound, as shown by tests on an injection-moulded air intake pipe for a car engine, fig. 6.12.
00
5 10 15 20 25 30 % 40
20
40
60
%
100
Regrind content
Rela
tive
chan
ge
Tensile strengthin accordance with ISO 527-1,2,initial value 115 MPa
Charpy notched impact strengthin accordance with ISO 179/1eA,initial value 20 kJ/m2
Fig. 6.6 · Change in tensile strength and Charpy notched impact strength as a result of
regrind addition
36
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
800300
1,000 1,600
400
500
600
mm
800
Injection pressure
Flow
leng
th
700
1,200 1,400 bar
Celstran PP-GF30-04
Celstran PP-GF40-04
Celstran PP-GF50-04
Celstran PP-GF30-03
Celstran PP-GF40-03
Fig. 6.7 · Flow lengths of the commercial Celstran PP grades
300
400
500
600
mm
800
Injection pressure
Flow
leng
th
700
Celstran PP-GF50-04
Tm = 290°C
Tm = 245°C
800 1,000 1,6001,200 1,400 bar
Fig. 6.8 · Influence of melt temperature Tm
on the flow length of Celstran PP-GF50-04
200900
400
500
mm
Injection pressure
Flow
leng
th
1,100 1,300 bar700
300
Celstran PA66-GF40
Tm = 320°C
Tm = 305°C
Fig. 6.11 · Influence of the melt temperature Tm
on the flow length of Celstran PA66-GF40-02
200900
400
500
mm
Injection pressure
Flow
leng
th
1,100 1,300 bar700
300
Celstran PA66-GF40
Celstran PA66-GF50
Fig. 6.10 · Flow lengths of Celstran PA66-GF40 and PA66-GF50
37
800300
1,000 1,600
400
500
600
mm
800
Injection pressure
Flow
leng
th
700
1,200 1,400 bar
Celstran PP-GF30-04
PP-GV30short fibres, easy flowing
Celstran PP-GV30-03
PP-GV30 short fibres
Fig. 6.9 · Flow lengths of Celstran PP-GF30 compared with PP with 30% by weight
short glass fibres
100.75
1.00
1.25
1.50
2.00
Fibre content
Ani
sotro
py
1.75
%15 20 30 40 30
long glass fibres
short glass fibres
Fig. 6.12 · Component anisotropy, determined from the ratio of the flexural modulus measured in
flow direction and transversely to it
6
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
6.2.6 Special methods
The usual special methods can be used for injectionmoulding Celstran. For example, the gas injectionmethod has proved successful for a gear lever, fig. 6.14.
Decorative effects can be achieved with two-colourinjection moulding. When multicomponent injectionmoulding is used, for example for producing combi-nations of hard and soft materials, the compatibilityand bond strength between matrix material and softcomponent must be borne in mind. Practical experi-ence has shown that Celstran PP can also be pro-cessed without any problems by foam injectionmoulding, fig. 6.15.
Virgin and recycled polyolefines are often processedinto complex large components by special methodssuch as transfer moulding, low-pressure injectionmoulding or intrusion. In such applications the effect of Celstran or Compel is to improve properties; anaddition of as little as 10 to 40% by weight givesthese components the required rigidity and strength.In addition, the stable parts are easier to demould,and so shorter cycle times are possible.
6.2.5 Gate and mould design
As with the injection unit, care must be taken toensure minimal shortening of the reinforcing fibres indesigning moulds. For this reason the diameters andradii of curvature of runners in flow direction and thecross-sections of gates must be dimensioned as largeas possible.
For Celstran PP and Celstran PA a central sprue gatehaving a diameter of at least 4 mm, better 6 mm, withall runners designed to promote smooth even flowhas proved successful. The diameter of the gateshould if possible be greater than 3 mm. Smallercross-sections (down to 1 mm diameter) can be cho-sen for blends with Celstran SF (stainless steel fibres).Pinpoint and film gates can be used with good resultsprovided they have adequately large cross-sections.
Hot runner technology for sprueless processing ofCelstran can readily be used provided open hot run-ner nozzles are used. If the recommendations forplasticizing and mould design are observed, a mould-ing is obtained with a fibre length distribution inwhich a high proportion of fibres are above the criti-cal length [7] (see section 1.3), i.e. with optimum reinforcing effect, fig. 6.13.
1Fibre length
Wei
ght c
onte
nt
5 10mm
Critical fibrelengthrange
3 mm0.8
Moulding
0
Fig. 6.13 · Indication of fibre length distribution of Celstran components: correctly produced moulding, critical fibre length range
drawn diagrammatically [7]
38
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
39
Fig. 6.14 · Gear lever made from Celstran PP-GF40 by gas injection moulding (manu-
facturer: Möller Plast GmbH, Bielefeld, Germany)
Fig. 6.15 · Pallet for the “Stecon”, returnable collapsible container made by foam injection moulding of Celstran PP-GF40, side walls and
cover compression moulded with Compel PP-GF30
6.3 Blow moulding of Celstran
Fundamental tests carried out by a machine manu-facturer have shown that long-glass-fibre-reinforcedplastics can be blow-moulded if a conventional blowmoulding machine is equipped with a special screwwith a gentle action for melting the pellets [8].
The long-glass-fibre-reinforced materials used for blow moulding normally have fibre contents bet-ween 5 and 30% [8]. To achieve these low contents acorresponding amount of Celstran with a higher fibre content is added to the unreinforced matrixmaterial by means of a metering unit.
6.3.1 Materials
The most important matrix material in blow mould-ing is PE-HD. For low fibre contents the blowmoulding grade normally employed for the unrein-forced blow-moulded part is used. Celstran PE-HD-GF60-01P10 is added to this material.
For higher fibre contents a PE-HD with a lower vis-cosity, i.e. with higher MFI, must be employed foruniform, gentle incorporation of the long-fibre mate-rial. In this case it is particularly important to ensurehomogeneous distribution in the melt of the fibrescontained in the added Celstran. This can be achievedby adapting the extruder temperatures. The long glassfibres give the melt the elasticity necessary for blowmoulding. With PP as matrix material blow-mouldedparts are obtained that withstand higher service tem-peratures.
As with PE-HD, Celstran PP-GF50 is added to a PPwith low melt viscosity via a metering and mixingunit so as to achieve the desired content of long glassfibres in the moulding.
Blow-moulded PP parts with long glass fibres aresuitable for applications in the engine compartmentof vehicles. Since they do not exhibit environmental stress cracking, they can also be used for mouldings in contact with fuel, lubricants or cooling water.
Because of their good strength even at elevated tem-peratures they are suitable for service temperatures up to 130°C under low load.
In the case of both PE-HD and PP the achievableblow-up ratio is lower with reinforced plastics thanwith standard blow moulding materials [8].
6
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
40
Coextrusion enables mouldings with an unreinforcedinner and outer layer to be produced by blow mould-ing. As a result the surface quality can be influencedwithin wide limits. Materials with a high glass fibrecontent can also be processed by this method [8].
6.3.2 Machine requirements
Celstran can be processed on commercial blowmoulding machines with single-screw extruders. Inselecting machine and screw care must be taken toensure that
- the material is melted gently so as to minimize fibredamage and
- the fibres remain uniformly distributed in the melt.
The screw must not have any shear elements, in particular no Maddock shear elements. Barrier-typescrews are also unsuitable because they cause con-siderable fibre breakage. Other mixing elementsshould also be avoided if possible. If it is necessary to use them, they should have an adequately largefree cross-section for the melt flow.
The screw diameter must be matched to the requiredthroughput; it should be at least 40 mm. In principlelarge screw diameters, low compression and lowspeeds should be employed so as to minimize shearenergy. The feed zone of the screw should be deep-flighted.
The compression ratio must not exceed 2:1.
The energy required for melting the pellets should ifpossible be provided solely via the barrel heating.Shear must be avoided. The extruder must not haveany screens or strainer plates because these can beblocked by the fibres.
6.3.3 Parison die
Celstran can be processed with continuous parisondies and with accumulator heads. The glass fibres give the parison increased rigidity in longitudinal and transverse direction. As a result the parison stretches less severely than in the case of unreinforcedPE-HD or PP.
The long glass fibres give the melt high rigidity. The diameter of the extruded parison should be aslarge as possible so as to minimize the blow-up ratio.The long glass fibres reduce parison swell markedly.
Fibre orientation in the component is influenced by the design of the flow channels in the parison die.The fibres are aligned in flow direction by means ofspider legs. This results in weld lines, which shouldbe located in component areas subject to low stress.Narrow flow channels also cause strong fibre orienta-tion in longitudinal direction. Layers with differentlyoriented fibres often form in the parison. In melt layers flowing near the wall the fibres are oriented inlongitudinal direction, whereas in the middle layerthey are oriented in circumferential direction.
6.3.4 Temperatures
The processing temperatures are governed by the plasticizing and homogenizing characteristics of themachine. Normally the material can readily be pro-cessed with a temperature profile similar to that forunreinforced PE-HD. Should poorly dispersed fibrebundles still be visible in the melt, the temperaturesmust be raised. In so doing, temperatures up to 50 Kabove those for unreinforced PE-HD are possible forthe rear extruder zones.
In the case of PP to which Celstran PP has beenadded it is advisable to use the temperature profilecommonly employed for unreinforced PP. The temperatures should be 240°C at the heating zone,230 and 220°C at the following zones and 210°C atthe extruder tip.
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
Fig. 6.16 · Drawing of a plasticizing/compressionmoulding machine, consisting of screw plasticizing
unit, vertical press and positive mould, for processing Compel [10]
Fig. 6.17 · Processing conditions for the plasticizing/compression moulding of Compel PP
6.4 Extrusion of Celstran
Extruded sheets and profiles can be obtained fromEnsinger GmbH, Nufringen, Germany. Coextrudedprofiles with a Celstran core and unreinforced innerand outer layers are supplied under the trade nameVHME (very high modulus extrudate) by IntekWeatherseal Product Inc., Hastings, Minnesota, USA.
6.5 Processing of Compel
6.5.1 Plasticizing/compression moulding
Because of its typical fibre length of 25 mm Compel is processed mainly by a gentle combination ofplasticizing and compression moulding [9]. A suitablemachine is shown in fig. 6.16 [10].
Procedure
Plasticizing/compression moulding comprises the following steps [10]:
1. The pellets are conveyed to the hopper and fed tothe plasticizing unit.
2. A deep-flighted screw plasticizes the materialgently. The screw then retracts and places the pre-pared melt in the enclosed space in front of it.
3. The plasticizing unit enters the opened mould.
4. The closure device at the plasticizing unit opens,the screw pushes the melt out and places it in theform of a strand in the mould.
5. The closure device at the plasticizing unit cuts offthe melt strand and the unit retracts from themould.
6. The press closes and the melt is distributed underfairly low pressure (typically 30 to 50 bar) andunder low shear stress in the cavity between thetop and bottom of the mould.
7. At the end of the cooling time the press opens.Parallel to this the plasticizing unit has preparedfresh melt.
8. The finished moulding is demoulded automaticallyor manually. With the placement of melt in themould the production cycle for the next mouldingbegins.
41
Melt temperature200 to 280°C, depending on the moulding
Mould temperatureup to 80°C
Closing speedas high as possible to prevent premature cooling
Compression speed≥ 5 mm/s, depending on the moulding
Specific cavity pressuredepending on the moulding
Cooling timenormally 15 s for 2 mm wall thickness,depending on the moulding
6
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
Machine and mould technology
The gentle plasticizing of Compel requires special plasticizing units with a screw diameter of at least 80 mm. Reductions in cross-section caused e.g. by inserts, nozzles or deflectors should be avoided.
The processing conditions for Compel PP are sum-marized in fig. 6.17. The rod-shaped pellets should be melted without compression. The back pressureshould be as low as possible. Cylinder temperaturesof 220 to 280°C can be used, depending on themoulded part geometry. The mould temperaturesshould be between 50 and 80°C.
The mould for shaping the parts must be designed as a positive mould, as in conventional compressionmoulding. The same design guidelines apply to ribs,drafts etc. as for Celstran. Components of complexgeometry, for example mountings and fascia panel supports for cars, can be made from Compel withoutany problems.
A vertical hydraulic press, if possible with synchro-nization control, is required to hold the mould and produce the locking force. Because of the relatively low cavity pressure locking forces of 8,000 to 30,000 kN are sufficient even for large mouldings.
Recycling
After compression moulding of Compel, waste frompunching operations is produced when openings arecut out in mouldings. This waste can amount to asmuch as 30% of the component weight. It can berecycled immediately in plasticizing/compressionmoulding provided it is granulated correctly: the finescontent in the granulated material must be low. Ourown investigations show that up to 30% waste frompunching operations can be added to a component,depending on the stress to which it will subsequentlybe subjected.
This and other facts of importance for recycling long-fibre-reinforced plastics are investigated in the project“Material recycling of long- and continuous-fibre-reinforced thermoplastics into high-quality, long-fibre-reinforced flow-moulded components” by the“Deutsche Bundesstiftung Umwelt”, Osnabrück,Germany. This project is a cooperative venture in-volving, among others, the “Institut für Aufbereitung(IFA)”, Aachen, the “Institut für VerbundwerkstoffeGmbH (IVW)”, Kaiserslautern, and the “Institut fürKraftfahrwesen Aachen (ika)”.
Further information on the processing of Compel isobtainable from Ticona.
6.5.2 Other methods
Apart from plasticizing/compression moulding, injection stamping is also suitable for processingCompel. Here too, gentle melting of the pellets by an adequately dimensioned screw (diameter at least80 mm) without a non-return valve and with lowback pressure must be ensured.
When the melt is injected into the still partly openedpositive mould, a low injection speed is essential forprotecting the fibres from damage.
6.6 Safety notes
Long-fibre-reinforced plastics, like many organicsubstances, are flammable (exceptions: Celstran PPSis not flammable, the Celstran PA6-CF30 andCelstran PC/ABS-GF40 grades are flame-retardantand reach UL 94 rating V-0).
It is in the interest of the processor when storing,processing or fabricating the material to take thenecessary fire prevention measures. Certain end products and fields of application may be subject to special fire prevention requirements.
The statutory safety regulations vary from one country to another. In each case the local regulationsare mandatory. It is the responsibility of the pro-cessor to ascertain and observe such requirements.Important information is given in safety data sheets,which are available from Ticona on request.
Due to danger of thermooxidative degradation notprocessed plastificates must always be cooled downcompletely in a water basin.
42
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
7. Finishing
7.1 Machining
The two most important methods of processing plas-tics, namely injection moulding and blow moulding,produce moulded parts that normally do not requireany finishing if the moulds are correctly designed.
Compression-moulded parts may require deflashingbecause material is unavoidably squeezed out of themould. In many cases the flash is removed with cut-ting tools.
Generally speaking, the high reinforcing fibre con-tent must be taken into account in milling, drilling orturning Celstran, Compel or Fiberod parts. In prin-ciple, tools with hard metal or diamond cutters arerecommended in order to achieve high-quality surfa-ces and long service life.
7.2 Assembly
7.2.1 Welding
Of the assembly techniques for plastic mouldings thevarious welding methods have achieved outstandingimportance.
Mouldings made from long-fibre-reinforced plasticscan be welded to each other or to parts made fromunreinforced or short-fibre-reinforced plastics. Thetype and quantity of reinforcing fibres must howeverbe taken into account in designing the weld area andin selecting the welding parameters.
In the case of glass-fibre-reinforced Celstran PP,regardless of the fibre content, heated tool weldingyields the highest values for weld strength. Themajor variables are given in fig. 7.1. The weldstrength achieved with Celstran PP is
- values between 25 and 40 MPa in heated tool buttwelding with the parameters given in fig. 7.2
- a tensile shear strength of about 15 MPa in heated tool lap welding under the conditions givenin fig. 7.3.
These values show that the weld strength is determi-ned basically by the matrix material.
43
Fig. 7.1 · Major variables on heated tool welding
Fig. 7.2 · Heated tool butt welding of Celstran PP
Material
· Density (type of fillerand content)
· Shear modulus (if possiblehigh and constant overtemperatureprofile)
· Viscosity(too low canlead to thematrix beingsqueezed outof the weldingzone)
Weldingparameter
· Surface temperature ofthe heated tool
· Heating pressure
· Heating time
· Welding pressure
· Welding time
Moulding
· Moulding rigidity
· Radius design(to avoid stress cracking> 5 mm)
· Weld geometry
Injectiongeometry
· Surface defects (voids)
· Dimensionalvariations(shrinkage,warpage)
· Processingdefects(demixing,decomposition)
· Internal stresses
· Moulding contamination(e.g. releaseagents)
F F
4
Weld strength: 25 to 40 MPa(depending on the glass fibre content, welding parameters,
moulding geometry, injection moulding)
orfor PTFE-coated
heated tool
Temperature of the heated tool: 260°C
Heating time: 10 to 20 s
Heating pressure: 0.5 to 0.6 MPa
Welding pressure: 0.5 to 0.6 MPa
for uncoatedheated tool
Temperature of the heated tool: 360°C
Heating time: 5 to 10 s
Heating pressure: 0.4 to 0.5 MPa
Welding pressure:0.4 to 0.5 MPa
Process variables
Recommended welding parameters
6
7
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
Vibration welding also gives good values for weldstrength. Values up to 25 MPa are achieved withCelstran PP under the conditions given in fig. 7.4.The weld strength is largely independent of the wel-ding depth, fig. 7.5.
In line with the higher strength of the matrix materialthe weld strength of Celstran PA rises to 45 to 55 MPa, fig. 7.6. Ultrasonic spot welding can be usedinstead of riveting. The characteristic welding para-meters and the achievable tensile shear forces areshown in fig. 7.7.
44
Fig. 7.3 · Heated tool lap welding of Celstran PP
FF4
415
Tensile shear strength: 15 MPa(depending on the glass fibre content, welding parameters,
moulding geometry, injection moulding)
for PTFE-coated heated tool
Temperature of the heated tool: 360°C
Heating time: about 20 s
Welding pressure: about 0.3 MPa
Fig. 7.4 · Vibration welding of Celstran PP
Linear movement
100
4
Weld strength achieved with
Celstran PP-GF40-04: about 21 MPaCelstran PP-GF50-04: about 17 MPa
00
0.5 4
10
20
30
Welding depth
Wel
d str
engt
h
mm
MPa
32.521.51
Celstran PP-GF40-04
Celstran PP-GF50-04
Fig. 7.5 · Weld strength as a function of welding depth of Celstran PP
0 0.5 3Welding depth
Wel
d str
engt
h
mm
MPa
21.510
20
40
60
Celstran PA66-GF50
Fig. 7.6 · Weld strength as a function of welding depth of Celstran PA
Recommended welding parameters
for Celstran PP, modification 04
Welding pressure: 1 MPa
Welding time: 5 s
Welding depth: about 2.0 mm
Recommended welding parameters
Celstran® Compel®
7.2.2 Adhesive bonding
In adhesive bonding of components made fromCelstran or Compel the matrix material is of crucialimportance. For instance, pretreatment of CelstranPP is necessary to lower the surface tension (coronadischarge, flame application) so as to obtain bondedjoints with adequate strength.
Bonded joints are simpler to produce with CelstranPA. Two-pack adhesives based on polyurethane andone-pack adhesives based on cyanoacrylate give goodresults.
long-fibre-reinforced thermoplastics (LFT)
45
Fig. 7.7 · Ultrasonic spot welding of Celstran PP
Recommended welding parameters
1.5 s
3 s
1.5
s
s
Sonotrode diameter: 4 mm
Amplitude: 0.05 mm
Ultrasonic exposure time: 1.2 s
Welding pressure: 0.25 MPa
Holding time: 3 s
Number of Tensile shear force in N wherewelding points s = 3 mm s = 4 mm
1 2800 3400
2 4500 5200
3 6200 8200
7
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
46
8. Recycling
Recycling of Celstran production waste (sprues, re-jects) is described in section 6.2.2 “Processing con-ditions”.
After use Celstran mouldings can be recycled. Themost important requirement is to segregate Celstranfrom other polymers. Celstran PP recyclate can beblended with other PP recyclates. An addition ofCelstran PP recyclate to unreinforced PP generallyimproves the latter’s properties because of the glassfibre reinforcement. The same applies to Celstran PA66 and PA66 recyclates. Further shortening of thefibres is likely in recycling, and so mouldings madefrom pure Celstran recyclates have poorer values thanvirgin Celstran material especially in impact strength.
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
47
Assembled Frontend for AUDI, Compel PP-GF40
Battery Tray for Opel Astra, Celstran PP-GF40
9. Photo supplement showingtypical applications
8
9
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
48
Lever for Electrical Cabinet,Celstran PA66-GF50
Housing Part for Seat Belt Mechanism,Celstran PA66-GF40
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
49
Mirror Bracket and Housing made fromCelstran PP-GF50 and Hostalen PPU
DEU Housing for Board Communicationin Airplanes, Celstran PPS-SF20
9
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
50
Tilt Tray Mechanism, Celstran PP-GF40 (company: WPK, Radevormwald)
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
10. Subject Index
abrasion, relative 27acoustic properties 29adhesive bonding 45anisotropy (shrinkage) 36
back pressure 35, 36blow-up ratio 39blow moulding 39, 40bonding 45burning-off (resin matrix) 6
chemical resistance 32coefficient of thermal expansion 27coloration 9colour masterbatches 9content of reinforcing material 10 – 19, 22continuous service temperatures 30, 39creep modulus 23 – 25creep properties 23, 25creep tendency 5, 23, 30
density 10 – 19, 21dielectric strength 28drilling 43drying 33 – 35
electrical insulation 28electrical properties 28electromagnetic shielding 28elongation at break 10 – 19, 31, 32enthalpy 27, 28environmental effects 30 – 32extrusion (Celstran) 41
fatigue strength 26fibre length 5, 6fibre skeleton 6, 20film gate 38finishing 43flammability 31flexural fatigue strength 26flexural modulus 10 – 19, 20, 22, 25, 31flexural strength 10 – 19, 31, 32flow path length 36flow properties 36fluctuating stress 26foam injection moulding 38form supplied 9fracture energy in puncture test 10 – 19, 25, 26
51
gas injection method 38gate design 38GMT compression moulding 6
heat ageing 30, 31heat deflection temperature 10 – 19, 30heated tool welding 43, 44hot runner technology 38hybrid reinforcement 9
impact strength 6, 10 – 19, 25, 32in-house coloration 9injection moulding 33 – 38injection moulding machines, equipment for 34injection pressure 36injection speed 35intrusion 38
literature 53long-fibre pellet 4, 6low-pressure injection moulding 38
material data 10 – 19matrix, thermoplastic 4mechanical properties 10 – 19, 21 – 27melt temperature (injection moulding) 34 – 37metering screw 33milling 43mould design (injection moulding) 38mould temperature (injection moulding) 34 – 36
nomenclature 8non-return valve 33notched impact strength 5, 10 – 19, 20, 25, 36
optical properties 28outer fibre strain 8 – 17overview of grades 5
parison die 40puncture test 10 – 19, 25, 26pinpoint gate 38plasticizing (Celstran) 34plasticizing/compression moulding 6, 41, 42preparation (processing) 33processing 33 – 42processing conditions (Celstran) 34 – 36
9
10
long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
processing conditions (Compel) 41, 42processing temperatures (Celstran) 35processing temperatures (Compel) 42properties, acoustic 28,
electrical 28mechanical 10 – 19, 21 – 27optical 29physical 20 – 29thermal 27, 28
pultrusion process 4
quality management 5
recycling (Celstran) 46recycling (Compel) 43regrind, addition 36
safety data sheets 42safety notes 42screws (blow moulding) 40screws (injection moulding) 33screw speed (injection moulding) 34 – 36shear modulus 30short-fibre pellet 4short-term stress 21, 22shrinkage 36, 38shut-off nozzles 38sliding properties 26sound deadening 29special methods (injection moulding) 38specific strength 20specific heat 27spiral test 36sprue gate 38strand sheating 4stress-strain curves 23, 30stress-strain diagrams 22surface properties 26
temperatures (blow moulding) 40temperatures (injection moulding) 34 – 36tensile modulus 10 – 19, 20, 22tensile strength 10 – 19, 20, 22, 36thermal conductivity 28thermal properties 27, 28thermoplastic matrix 4toughness 25, 26, 30transfer moulding (Celstran) 38transfer moulding (Compel) 42turning 43two-colour injection moulding 38
UL rating 31ultrasonic welding 43, 44
vibration welding 43, 44volume price 21
warpage tendency 36water absorption 10 – 19wear 26, 27wear resistance 33welding 43, 44weld strength 43, 44
52
Celstran® Compel®
long-fibre-reinforced thermoplastics (LFT)
11. Literature
[1] Lücke, A.: Thermoplaste mit Rückgrat.Kunststoffe 87 (1997) 3, p. 279 – 283
[2] Lücke, A.: Eigenschaften und Anwendungenvon langfaserverstärkten Thermoplasten. In: Zepf, H.-P. et al.: Faserverbundwerkstoffemit thermoplastischer Matrix. Reihe Kontakt & Studium, vol. 529, Expert-Verlag, Eßlingen 1997
[3] Lücke, A.: Long Fiber ReinforcedThermoplastics in Cars. In: Handbuch zur 18th SAMPE EuropeInternational Conference, Paris 1997
[4] Pfeiffer, B.: Konstruktionswerkstoffe mitEdelstahlfasern gefüllt. In: Handbuch zum 7. SymposiumElektrisch leitende Kunststoffe, TechnischeAkademie Eßlingen 1997
[5] Pfeiffer, B.: EMI-Shielding mit Edelstahl-filamenten.Plastverarbeiter (1997)
[6] Dr. Edward M. Silverman: “Creep and ImpactResistance of Reinforced Thermoplastic:Long Fibers vs. Short Fibers”SPI/RPC 1985
[7] Wolf, H. J.: Personal communication from theDKI, Darmstadt
[8] Thielen, M.: Starke Hohlkörper. Kunststoffe 84(1994) 10, p. 1406 – 1412
[9] Thomas, G.: Entwicklung kostengünstiger,serientauglicher Plastifizier- und Preßver-fahren zur Herstellung von Strukturbauteilenaus anwendungsspezifisch entwickelten,unidirektional langfaserverstärktenThermoplast-Granulaten.Abschlußbericht der Hoechst AG zumBMFT-Projekt 03 M 1055, Frankfurt 1996
[10] Plastifizier-/Preßanlage – Verarbeitung thermoplastischer Kunststoffe im Strang-ablegeverfahren.Firmenschrift der Kannegießer KMHKunststofftechnik GmbH, Minden 1997
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long-fibre-reinforced thermoplastics (LFT)
Celstran® Compel®
Important: Properties of molded parts can be influ-enced by a wide variety of factors involving materialselection, further additives, part design, processingconditions and environmental exposure. It is the obligation of the customer to determine whether aparticular material and part design is suitable for aparticular application. The customer is responsiblefor evaluating the performance of all parts containingplastics prior to their commercialization. Our pro-ducts are not intended for use in medical or dentalimplants. Unless provided otherwise, values shown
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merely serve as an orientation; such values alone donot represent a sufficient basis for any part design.Our processing and other instructions must be fol-lowed. We do not hereby promise or guarantee spe-cific properties of our products. Any existing indu-strial property rights must be observed.
© Copyright by Ticona GmbH
Published in December 2000
Cel
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® L
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-rei
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Ticona GmbHCustomer Service EuropeD-65926 Frankfurt am MainTel.: +49 (0) 69-3 05-8 47 32Fax: +49 (0) 69-3 05-8 47 35
Hostaform® POM
Celcon® POM
Duracon® POM
Celanex® PBT
Impet® PET
Vandar® Thermoplastic polyester blends
Riteflex® TPE-E
Vectra® LCP
Fortron® PPS
Topas® COC
Celstran® LFT
Compel® LFT
GUR® PE-UHMW
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Technical InformationTel.: +1-8 00-6 33-48 22
Customer ServiceTel.: +1-8 00-6 33-48 22