Supporting material for students registered to subject:
Macromolecular chemistry S112003
Teacher: Jan Merna, Department of Polymers, Institute of Chemical Technology ,Prague
Lecture authored by Jan Merna is licensed under a Creative Commons Attribution-
NonCommercial-NoDerivs 3.0 Unported License
Sources:
Prokopová I.: Makromolekulární chemie, VŠCHT Praha, 2007. (educational text in Czech)
Merna J.: Polymers Instantly, educational text in English, freely accessible from
http://merna.eu/teaching/macromolecular-chemistry/
Encyclopedia of Polymer Science and Technology, J.Wiley Sons, Interscience, Publ., New York, 1964-1991
[email protected], B130
Lectures + exercises (2+1)
Recommended literature:•Stevens M.P.: Polymer Chemistry� An Introduction. Oxford University Press, Inc.,
New York 1999.
•Chanda M.: Introduction to Polymer Science and Chemistry. A Problem Solving
Approach. CRC Press Boca Raton 2006.
•Young R.J., Lovell P.A.: Introduction to Polymers. Third Edition. CRC Press Boca
Raton 2011.
Supporting materials: http://merna.eu/teaching/macromolecular-chemistry/
Evaluation:
written tests:
•One test in the mid of semester•Final exam test
MACROMOLECULAR CHEMISTRY
Outline of the course:
1. Basic terms, history, nomenclature
2. Structure of macromolecules, molecular weight.
3. Molecular structure and properties of polymers.
4. Polymerizability of low molecular substances.
5. Free radical polymerization - elemental reactions.
6. Kinetics of free radical polymerization.
7. Free radical copolymerization.
8. Ionic polymerization and copolymerization.
9. Insertion polymerization, polymerization practice.
10.Ring-opening polymerization.
11.Step-growth polymerization - characterization, reactivity of
monomer functional groups.
12.Polycondensation - mechanism and kinetics, molecular
weight distributions.
13.Polyadditions - typical syntheses.
14.Reactions of polymers.
(1838) polyvinylidenchloride
(1839) polystyrene ?
1820 processing of natural rubber
1839 rubber vulcanization
1862 celluloid- nitrocellulose+camphor
1897 Galalith - casein (milk protein) and formaldehyde
HISTORY OF MACROMOLECULAR CHEMISTRY
1906 Bakelite – phenol-formaldehyde resin
1915 „methyl-rubber “ - poly(dimethylbutadiene)
1926 – 1939 alkyd resins, aminoplastics, polymethylmethacrylate, polybutadiene, polyvinylacetate, polystyrene, polyvinylchloride, polyethyleneoxide, polychloroprene, unsaturated polyesters, polyizobutylene, butadiene-styrene rubber, polyamide 66
1939 – 1945 polyvinylidenchloride, PE (LD), polyamid 6, polyurethanes, polyakrylonitrile, silicons
1946 – 1955 epoxides, polytetrafluorethylene, polyethylenterephtalate, polycarbonates, PE (HD)
1956 – 1965 polybutadiene (cis-1,4), polypropylene, polyformaldehyde,aromatic polyamides, block copolymers Sty-Bu-Sty
HISTORY OF MACROMOLECULAR CHEMISTRY
Fathers of macromolecular chemistry
Wallace Carothers (1896-1937)Hermann Staudinger (1881-1965), NP 1953
Paul J. Flory (1910-1985), NP 1974
theory of polycondensation
solution and solid phase polymer properties,
theory of crosslinkingKarl Ziegler Giulio Natta, NP 1963
1950
1960
1970
1980
1990
2000
2010
0 2 4 6 8
Year
Nobel prices in polymer science
Natta & Ziegler
Heeger & MacDiarmid
& Shirakawa
Polymer production worldwide
300 Mt/year (7% of oil)
1. PE 80 Mt/y
2. PP 50 Mt/y
3. PET 50 Mt/y
4. PVC 30 Mt/y
5. PS-styrene polymers
Rubbers- 20 Mt/y
Price of basic polymers
1-2 €/kg
Age of plastics
Polymers advantages and role in today‘s society:
•Low density•Cheap manufacture and sources•Easy processing•Insulation properties-thermal+electro
•Polymers save more energy than used for their production(buildings, transportation)•Food protection•Fabrics-synthetic fibres-save land, fertilizers, water
Utilization of plastics in Europe:
Plastics classification:
•Consumable (commodity)_PE,PP,PS, PVC, PET
•Engineering (construction) plastics-better properties
•Special (high-performance)P
ric
e +
pe
rfo
rma
nc
e
Pro
du
cti
on
vo
lum
e (
t/y)
Thermoplastics classification
Special
Engineering
Commo
dity
Plastics recycling in Europe
polymer ( macromolecular compound)
Oligomer
monomer
polymerization
polyreaction
step-growth
chain-growth
ring-opening
regular (irregular) polymer
constitutional unit
Constitutional repeating unit (CRU)
Monomeric unit (mer)
Polymerization degree
Copolymer
Basic terms
CH2 CH
Amonomer
polyreactionCHCH2 CHCH2 CH2 CH
A A ARegular polymer
CHCH2 CH2 CH2CHCH
AAAIrregular polymer
CHCH2
A
CH2CH
A
Repeating constitutional units (CRU)
,CH2
constitutional unit
CH
A
CHCH2 CH2
A
CHCH2 CH2
A
,, , ...
n
CH2 CH2CH2 CH2
monomer (ethylene) Polyethylene with degree of polymerization n
CRUCH2
Monomeric unitCH2CH2
Basic terms
IUPAC. Pure Appl. Chem. 84, 2167–2169 (2012).
Polymer nomenclature
PRINCIPALS OF STRUCTURE BASED POLYMER NOMENCLATURE
The order of subunit seniority in preferred CRU: 1. heterocycles
2. heteroatoms3. C-cycles4. C-chains
Naming of pref. CRU: listing of names of largest possible subunits
CRU usually divalentC atom with double bond have the lowest locant number
free valences in C-cycles – lowest locant numbers
• Choice of preferred CRU
• Naming of CRU (according to nomenclature rules of org. chem.)
• prefix poly-
Polymer nomenclature
>
1. podjednotka s největším počtem kruhů
poly(4,2-pyridindiylimino-1,4-phenylene-benzylidene)
N NNHNH CH CH
Hierarchy of heterocyles
More unsaturated (less hydrogenated) unit is favoured
Hierarchy of heteroatoms
O,S, Se, Te, N, P, As, Sb, Bi, Si, Ge, Sn, ….
Hierarchy of C-cycles
1. Subunit with largest amount of cycles
>
2. podjednotka s největším individ. kruhem
>
3. podjednotka s největším počtem atomů společných dvěma cyklům
> >
5. podjednotka nejméně hydrogenovaná
4. podjednotka s nejnižšími čísly lokantů v prvním rozdílném bodě
spojení kruhů
10a
>
8a
5a
1
2
3456
7
8
9 10
1 2
3
4
10
56
7
8
98a
2. Subunit with the largest individual ring
3. Subunit with the highest number of common atoms between two cycles
4. Subunit with the lowest number of locants in first different point of cycles connection
5. The most unsaturated cycles is the most preferred
Substituents
n
CH2CH
BrCl
1 3
5
2
46
a) Included to trivial name of subunitb) Named using prefixes joined to the name of corresponding subunit
poly[(6-chlorocyklohex-1-ene-1,3-diyl)(1-bromoethylene)]
poly[(6-chlorocyklohex-1-ene-1,3-diyl)(1-bromoethanediyl)]
Functional derivatives as a part of CRU
as substituents ad b)
poly[oxy(2-methoxycarbonyl)ethane-1,1-diyl]
- chemical
constitution
- type and arrangement of structural units - molar mass
configuration
conformation
- physical
mutual arrangement of macromolecules
2. STRUCTURE OF POLYMERS
1. Constitution
Monomer with functionality two : linear polymers (a)
Monomer with functionality two or higher : branched (b)
crosslinked polymers (c)
(a) (b) (c)
Types of enchainment of monomer units
R
CH CH2
CH2
RHCR R
CH CH2 CH CH
2
CH2
R
CH CH2
R R
CHCH CH2
Connection head to tail
Connection tail to tailResp. head to head
Modes of monomer units connection for conjugated diene
polymerization
1
2
3
4
2-methylbuta-1,3-diene isoprene
1
4
12
34
1,2-addition
1,4-addition
n
3,4-addition
Non-symetrical substituted diene: isoprene
symmetrical diene: butadiene
CH2CH2 CH CH
CH2CH2 CH CH
CH2
CH2 CH
CH
1,4 - addition
1,2 - addition
(the same as 3,4-addition)
Special macromolecular architectures
Grafted-copolymercomb
star
dendrimer
ladder
cyklic
polycatenane
polyrotaxane
Copolymers:
statistical
alternating
block
grafted
Reasons for spatial isomers:
a) tetrahedral arrangement of substituents on asymmetrical carbon atom
zig-zag conformation of polyethylene
2. Macromolecules configuration
Reasons for spatial isomers :
b) Planar arrangement of substituents on carbon atoms connected by double bond
cis isomers
trans isomers
- arrangement (sequence) of stereoisomeric centers
Atactic polymer
R RR R RR
isotactic polymer syndiotactic polymer
Polymer tacticity
Ditactic polymers
erythro-diizotactic threo-diizotactic
erythro-disyndiotactic threo-disyndiotactic
R H H HRR R
H H H
H
HR RH H
H H
H H
H H
R R R,
R,
R,
R,
R,
R,
R,
R,
Ditactic polymers
R H H H HR R
H H H H
R
H
R
H H H H H H H
R R R
R,
R,
R,
R,
R,
R,
R,
R,
erythro-diizotactic threo-diizotactic
erythro-disyndiotactic threo-disyndiotactic
synperiplanar (sp) antiperiplanar (ap)conformation conformation
3. Molecule conformation
Ethane
sp ap
H
H
H
H
H
H
HH
HH
HH
H H
H
H H
H
H H
H
H
H
H
Angle of rotation
180°sp
-180°sp
-120°ap
-60°sp
0°ap
60°sp
120°ap
Potentialenergy
Molecule conformation
Butane
least probable! !
Rotational movement of atoms in polymer chain
1
2
3
4
5
Free rotation is restricted by stericbarriers and by interaction with neighbor macromolecules
Chain segment
rotating part of chain (between nodes)
Dimensions of macromolecular coil
rmax
r = 0
oo
r opt
Average end-to-end distance
ideal chain (freely-jointed chain)
Polymer: mixture of polymerhomologues – nonuniform polymer
n1, n2, ...ni – number of molecules
M1, M2, ...Mi – molar mass of molecules
Types of average molar mass of polymers
- number
- mass (weight)
- viscosity
- z-average
ii
i
iin Mx
n
MnM
ii
ii
2
iiw Mw
Mn
MnM
a
1a
iiv MwM
ii
2
ii
2
ii
3
iiz
Mw
Mw
Mn
MnM
Molar mass of polymers
Uniform polymer: all macromolecules are of the same size
Relationships between molar mass averages:
zwn MMM
zwn MMM
< <
Uniform polymer
Non-uniform polymer
Analogy of polymer molar mass
498 pcs à 1 kg = 498 kg2 pcs à 250 kg = 500 kg
500 pcs 998 kg
400 pcs à 1 kg = 400 kg100 pcs à 6 kg = 600 kg500 pcs 1000 kg
kg1,9962498
kg250)x21x(498Mn
kg2,00
100400
kg6)x1001x(400Mn
kg125,75250x21x498
kg)250x21x(498M
22
w
kg4,00
6x1001x400
kg)6x1001x(400M
22
w
-the relationship between the number of moles of each polymer species (ni) and the molar mass (Mi) of that species
Am
ou
nt
of
poly
mer
Mol. mass
nM
wM
zM xi
0Mol. mass
Distribution of polymer molar mass
Methods of molar mass determination
Mn: osmometry, ebulioscopy, cryoscopy, determination of end-groups
Mw: light scattering
Mv: viscometry
Determination of molar mass distribution:
Size exclusion chromatography-SEC (gel permeation chromatography-GPC)PS calibration x absolute detection
Separation mechanism of SEC
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