Brilliant Polymer Scientist-Nantes-2011

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Some brilliant Polymer Scientist and brilliant Polymer Science.

ByProfessor Malcolm Mackley

Department of Chemical Engineering and Biotechnology

University of Cambridge UK

Nantes September 2011

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3

Brilliant Polymer Scientist, 1

1940s

W and H Kuhn

Swiss Physical Chemists

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1940s, Werner and Hans Kuhn

Werner Kuhn Hans Kuhn1900 1950 2000 2010

WK HK

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d)rb(b

d)z,y,x(P 222/3

3

R0

a

n links

Root mean square end to end distance

1/20

1/22 n a Rr

1934 Kuhn Random Coil

d))z,y,x(Pln(kS

22rkbcS

22

na2

3b

Probability distribution

Entropy

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Rubber Elasticity Kuhn and Treloar 1950s

1

2

3

N crosslinks /unit volume

)3(NkT2

1W 2

322

21

)3(Nk2

1S 2

322

21

STw

1dw 1321

)1

(NkT21

1

Entropy change

Energy change entropic

Incompressible Mechanical work

Constitutive equation

Molecular - Macro

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Brilliant Polymer Scientist, 2

1950- 70s

Andrew Keller

Hungarian Physical Chemist

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Andrew Keller

1900 1950 2000 2010AK

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Andrew Keller

• Polymer crystallisation

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Polyethylene single crystals

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1955-1990s Polyethylene solution crystallisation

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1980 Polyethylene nano and microstructure

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Low density polyethylene AFM

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Brilliant Polymer Scientist, 3

1970- 2000s

Pierre de Gennes

French Physicist

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Pierre de Gennes

1900 1950 2000 2010PdG

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Pierre de Gennes

• Superconductivity

• Liquid crystals

• Polymers

• Soft Matter

17Graphic courtesy of Alexi Likhtman, University of Reading

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Polymer Reptation

3n 0

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Linear viscoelasticty of polymer melt

10

100

1000

10000

100000

0.1 1 10 100 1000frequency (rad/s)

G' (

Pa

), G

'' (P

a),

*

(Pa

.s)

G'G''eta*

1

10

100

1000

10000

100000

0.001 0.01 0.1 1 10 i (s)g

i (P

a)

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Multimode Pom-Pom model

Viscoelastic stress:

Backbone orientation:

Stretch:

Time scales:

1988 McLeish and Larson

McLeish, TCB Larson, RC J. Rheol. 42, 1 81-110 (1998)

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22dP = 3.96 bardP = 3.76 bar

Vp = 0.44 mms-1

3D simulation Experiment

3D EUsolve

Polystyrene (PS2)

10mm depth

LHS Pom Pom

RHS Experiment

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Brilliant Polymer Scientist, 4

1950- 1980s

Sir Charles Frank

English Physicist

1900 1950 2000 2010FCF

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Sir Charles Frank

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Sir Charles Frank

• Dislocations; Frank-Read source

• Liquid crystals; Frank elasticity

• “Meson catalysed Cold fusion”

• Polymer crystallisation

• High modulus polyethylene

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Polyethylene

Diamond

ExpectE=285 GPaNot usualE=1 GPa

Frank 1970

Bunn 1934

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The stretching of Polymer; Chains Peterlin and Ziabicki 1960s

PolymerChain extension

chainpolymer of time relaxation chain τrate, strain γ γ β

number criteria for polymer chain extension 1

Kinetic Theory of Kuhn and Kuhn 1940s

Kuhn and Kuhn 1940s

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Chain extension with opposed jets

B number criteria for chain extension 1

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Localized Flow Birefringence of Polyethylene Oxide Solutions in a Four Roll Mill 1974

Crowley et al. Journal of Polymer Science: Vol 14 1111-1119 (1976)

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x0 ,y0

x1 , y1

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1

0 t

B number criteria for chain extension

Strain criteria for chain extension

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Shish KebabCore;Extended chain

Shish Kebab Polyethylene fibrous crystalsSolution processing.

Mackley 1970

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Brilliant Polymer Scientists, 5

1980s

Piet Lemstra and Paul Smith

Dutch Polymer Scientists

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Paul Smith.Now ETH

Piet LemstraNow TU Eindhoven

Smith and Lemstra 1980

1900 1950 2000 2010

35P. Smith, and P.J.Lemstra, J. Material. Sci. 1980, 15, 505

1. Low entanglement UHMWPE polymer gel

2. Unoriented Gel fibre

Quench bath

3. Unoriented Low entanglement semi crystalline fibre

4. Hot draw

5. Oriented High Modulus Polyethylene

Solvent recovery

Piston

Low entanglement,Gel Drawing

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Continuous processing of UHMWPE Dyneema

Screw extruder

UHMWPE Polymer powder SolventLow entanglement polymer gel

Spinneret

Gel fibres

Quench bath

Low entanglement semi crystalline fibre

Hot draw

Solvent recovery

High Modulus Polyethylene

Smith and Lemstra J Mat Sci 1980

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2000Whitstable UK

Mackley 2000

DyneemaHigh moduluspolyethyleneropes

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Common Factors

• Intelligence

• Genuine interest, motivation

• Physical and Scientific insight

• Appreciation of both experimental and theoretical aspects

• Something special