Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.
-
Upload
brianne-lucas -
Category
Documents
-
view
239 -
download
0
Transcript of Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.
![Page 1: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/1.jpg)
Micro-scale Polymer Processing:Multiscale Modelling of Entangled Polymers
![Page 2: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/2.jpg)
Polymer Processing in the 21st century?
Reaction Chemistry
Molecular shape
“Good processing”
Melt Rheology
![Page 3: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/3.jpg)
Industrial LCB and the “Buffer Zone”
THEORY MODEL MATERIALS INDUSTRIAL RESINS
18 20 22 24 26
0.0
0.2
0.4
0.6
0.8
1.0
RI
(rel
ativ
e in
ten
sity
)
Retention time (minutes)
DOW680E 200k before 200k after
103
104
105
106
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2Model distribution for CM3
MW
Fre
quen
cy
102
104
106
108
10-4
10-1
102
105
108
G'(
), G
''()
0
2
4
6
-5 0 5 10
log
log
G'(
), G
''()
![Page 4: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/4.jpg)
Polymer characterisation
Synthesis Scale up
Advanced RheologicalCharacterisation
Model ProcessingFlow Rig
Materials testingSolid stateModelling
Flow computation
Molecular Theory
Molecular ConfigurationProbes
Synthesis
Rheology
Processing
Properties
INDUSTRY
The Scaffold Concept
![Page 5: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/5.jpg)
• “Follow the processing path of well characterised polymers from synthesis through processing and property evaluation combined with the parallel development of a mathematical and computational protocol.”
Polymer characterisation
Synthesis Scale up
Advanced RheologicalCharacterisation
Model ProcessingFlow Rig
Materials testingSolid stateModelling
Flow computation
Molecular Theory
Molecular ConfigurationProbes
The Principle
![Page 6: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/6.jpg)
The Team• Leeds
– Tom McLeish, Oliver Harlen, David Groves, Alexei Likhtman, Tim Nicholson, Alan Duckett, John Embery, Jorge Ramirez, Chinmay Das, Harley Klein, Dietmar Auhl
• Bradford– Phil Coates, Tim Gough, Mike Martyn, Rob Spares
• Durham– Lian Hutchins, Nigel Clarke, Eduardo de Luca
• Sheffield– Tony Ryan, Ellen Heeley, Patrick Fairclough, Ron Young,
Christine Fernyhough
• Cambridge– Malcolm Mackley, Karen Lee, Ashish Lele, Mark Collis, David
Hassell
• Oxford– Paul Buckley, Junjie Wu, David de Foccatis
![Page 7: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/7.jpg)
Polymer characterisation
Synthesis Scale up
Advanced RheologicalCharacterisation
Model ProcessingFlow Rig
Materials testingSolid stateModelling
Flow computation
Molecular Theory
Molecular ConfigurationProbes
flowSolve
Tube models:LCB: Pom-Pomlinear: ROLIEPOLY
Cambridge MPR4/Bradford-Durham recirc.
Durham SANSSheffield SAXS
hPS+dPS linears +3 blendsPB combs PB linears + hPB variants
G*, shear transients, step shearMeiner extensional
Ox ford ModelCompressionCrazeBirefringence
Outline
![Page 8: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/8.jpg)
Synthesis Platform
• Make polybutadiene in controlled fashion
sec-Bu-Li+ +
1,4-polybutadiene (cis- and trans-)
1,2-polybutadiene
93%
7%
n
m
-
Li+
– Polydispersity < 1.05– Molecular weight determined by reagent quantities– Micro-structure affected by temperature, solvent
• Then hydrogenate to make polyethylene
![Page 9: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/9.jpg)
Update on tube model physics:Reptation + Contour Length Fluctuation + Constraint Release
Molecular Theory Platform
![Page 10: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/10.jpg)
)','(ln'
)',('
),(ln)',(2
1
)('2
3)(
')',(
'
2
2
2
2
2
ssftrs
ssfs
ssftrs
ssfs
ffss
ffffss
ssDsst
f
e
eqT
eq
)','(ln'
)',('
),(ln)',(2
1
)('2
3)(
')',(
'
2
2
2
2
2
ssftrs
ssfs
ssftrs
ssfs
ffss
ffffss
ssDsst
f
e
eqT
eq
Reptation +CLF flow CR
retraction
Detailed Chain FormulationGraham, Likhtman, Milner, TCBM
zdsssf
s
tsR
s
tsRtssf
0),(;
'
),'(),(),',(
z
dsssfs
tsR
s
tsRtssf
0),(;
'
),'(),(),',(
s
R(s)
![Page 11: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/11.jpg)
Log(w)43210-1-2-3-4
Lo
g(G
'(w
),G
''(w
))
7e0
6e0
5e0
4e0
3e0
2e02
taue=0.0030221
5.756 Ge=5.6985E5
log [s-1]
lo
g G
‘, G
‘‘ [
Pa
]Linear shear rheology andpredictions
µPP2 software tool: RepTate
Lines are predictions from linear theory (Likhtman & McLeish 2002)
Model Parameters from linear theory:(Likhtman & McLeish 2002)
e (25°C) = 0.003 s
Ge (25°C) = 0.569 MPa
Me = 4.86 kg/mol
cv = 0.1
Tref. = 25 °C
PI-4kPI-14kPI-30kPI-90kPI-200k
![Page 12: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/12.jpg)
• Solve momentum and mass conservation equations:
where is the polymeric stress
Flow solving Platform
• Constitutive equation can be used to calculate polymer stress.
• Develop a Lagrangian finite element flow solver whose
moving triangular grid elements can hold the constitutive parameters (orientation and stretch for each mode).
2u p
u 0
b,s,S,=>
u,p
u,pu,p
Nicholson, Bishko, Harlen
![Page 13: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/13.jpg)
flowSolve output – planar flow
• The recirculating vortex in the corner grows considerably as the simulation proceeds.
• The maximum stretch is not along the centre line, but lies between the centre line and the recirculating region where the material is sheared prior to extension.
![Page 14: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/14.jpg)
MuPP2 Structure
A Matrix approach to Industrial demand and technical opportunity
Platform I: Synthesis and Characterisation
Platform II: Theoretical Molecular Modelling
Platform III: Experimental Probes
Platform IV: Flow Visualisation
Platform V: Solid State Properties
Stm1: CRYSTAL Stm2: TOOLBOX Stm3: 2-PHASE
![Page 15: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/15.jpg)
MuPP2 Management
+ Special task groups:• Rheology team• Synthesis team• Solid State team• Flow solving software team• PDRA conference
![Page 16: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/16.jpg)
EXPERIMENTAL DATA
Text, binary file*.txt, *.dat, *.out…
ToolBox
Need to visualize
w0.001 0.01 0.1 1 10 100 1,000
G'(
w),
G''(w
)
1e2
1e3
1e4
1e5
1e6DIFFERENT
VIEWS
Gnuplot, Origin, Excel, Matlab, Xmgr…
THEORIES
Reptation CLFDTD CCRSCCR Rolie-Poly…. Pom-Pom
Set of equations to solve.Program in C, Fortran, C++, Pascal, Maple, Matlab, Mathematica…
Need to compare
![Page 17: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/17.jpg)
2PHASE: Mesoscale SimulationsTwo-dimensional simulations of freely suspended particles in a polymeric fluid under shear flow.
Biperiodic lattice to extend a unit cell containing N particles to an infinte domain.
•Under shear these cells slide
• relative to one another.
O. Harlen and A. Malidi
![Page 18: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/18.jpg)
CRYSTALShear-induced crystallization of comb 10
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
0 200 400 600 800 1000 1200 1400
Time /sec
No
rmal
ised
inte
nsi
ty /A
rb
363K iso
368K iso
363K shear
368K shear
370K shear
363K 1020 s
sheared at 100 s-1 for 5 s prior to crystallisation
• Massively increased rates after shear
• Well oriented crystals (no shearing during crystallisation)
54 kg mol-1 backbone with 8 arms of 15 kg mol-1
No shear
![Page 19: Micro-scale Polymer Processing: Multiscale Modelling of Entangled Polymers.](https://reader030.fdocuments.us/reader030/viewer/2022033017/56649e035503460f94aedc1d/html5/thumbnails/19.jpg)
• Model materials refine new entanglement physics
• Molecular structure has flow-field consequences
• Chain orientation is a family of numbers
• Routes to Polydisperse architectures
• Methodology extends to product structure in phase
and crystallinity.
Conclusions