On the Coarsening of Cocontinuous Polymer Blends€¦ · Laser Scanning Confocal Microscopy (LSCM): 3D Imaging 11. Fluorescent‐Dye Monomer (AMMA) Synthesis: FL‐Polystyrene synthesis

On the Coarsening of Cocontinuous Polymer Blends

Carlos R. López Barrón

Ph.D. Thesis DefenseNov. 18th, 2009

1

Cocontinuous Structures

2

Applications

Conductive blends for controlled dissipation of static charges

3

Applications

Membranes and porous media for separation and filtration

Jacoby, 2006

4

Applications

Washburn et al., J Biomed Mater Res, 2002

Tissue engineered scaffolds

5

Desiccant entrained polymers

US Pat. No. 5,911,937 ‐ Base Polymer (PE, PP, Nylon, etc)‐ Channeling Agent (EVOH, PVOH)‐ Desiccant

Mixing

Phase Separation

Applications

6

‐ Base Polymer (PE, PP, Nylon, etc)‐ Channeling Agent (EVOH, PVOH)‐ Desiccant

Mixing

Phase Separation

Container Liner

http://www.csptechnologies.com/

Aluminum Pouch Inserts

Films

Applications

Desiccant entrained polymers

US Pat. No. 5,911,937

7

20 m

20/80 PS/SAN Blend

50 m

50/50 PS/SAN Blend

Cocontinuous blends are

not in thermodynamic

equilibrium

50 m 20 m

Annealing for 20 min at 200 °C Annealing for 45 min at 200 °C

The Coarsening Problem

8

Outline

1. Coarsening dynamics• 3D imaging +Image analysis

2. Morphology control• Addition of block copolymer

3. Rheological response• Non‐Compatibilized and compatibilized blends

• Relate Morphology‐Rheology9

Olympus Fluoview 1000

Drawbacks:

1. Visible depth depends on sample transparency

PMMA/SAN20nPMMA‐nSAN =0.1

PS/SAN20nPS‐nSAN =0.02

System: PS(n = 1.59)/SAN(n = 1.57)

Laser Scanning Confocal Microscopy (LSCM):

3D Imaging

10


Drawbacks:

1. Visible depth depends on sample transparency

2. Need fluorescently labeled blends

System: PS(n = 1.59)/SAN(n = 1.57)

Fluorescent dye


3D Imaging

11

Fluorescent‐Dye Monomer (AMMA) Synthesis:

FL‐Polystyrene synthesis (by radical polymerization):

FL‐PS Synthesis

12

FL‐ PS SAN

Blends:

Polymer AN‐content(% mole)

MW (Kg/mol)

η(Pa‐s)

FL‐PS 40K ‐‐‐ 40 80

FL‐PS 120K ‐‐‐ 120 1500

FL‐PS 200K ‐‐‐ 200 6900

SAN10 9.5 135 2100

SAN20 19.3 115 2350

SAN 30 28.9 100 2500

Materials

13

200 °C

‐Daca Micro‐Compounder‐Vertical TSE w/recirculation

‐ 4g batches

‐mixing for 10 min at 100 rpm and 180 °C

‐ Blends with 50/50, 35/65, 20/80 w/w

‐Annealing: ‐ Quiescent annealing @ 200 °C

‐ Quenched after different times

Pellets

Blend Preparation

14



Stack of images:

3D Imaging

15

ThresholdedDeconvoluted 3D ImageOriginal from LSCM

Image Processing:

3D Reconstruction

Why 3D images?

3D Imaging

16

50 m 17

18

19

20

21

Lopez‐Barron and Macosko, Langmuir 2009 22

23

24

25

Outline





PS/SAN20 50/50 Blend

5 min 10 min 20 min

50 m 50 m 50 m

Coarsening

27

0 50 100 150

0

20

40

60

80

1/Q

, m

time, min

Q Interfacial area p.u.v. Siggia, 1979

Pin

PP

2a

PS/SAN20 50/50

1ddz a

P

Coarsening

28

PS/SAN20 50/50

Q Interfacial area p.u.v.

0 50 100 150

0

20

40

60

80

1/Q

, m

time, min

1ddz a

P

Pin

PP

2a

Siggia, 1979

Pin

PP

2a

2

:8 8a d aPoiseuille v

dz

P

: ,Assumptions a v d dt

Coarsening

29

Pin

PP

2a

0 50 100 150

0

20

40

60

80

1/Q

, m

time, min

1 ~Avg

c tQ

Siggia, 1979

Pin

PP

2a

PS/SAN20 50/50

~ 0.1 t


Coarsening

1ddz a

P

30

1dz a

Hd

P

Pin

PP

2a

Siggia, 1979

Pin

PP

2a

PS/SAN20 50/50

~ 0.1 t


0 50 100 150

0

20

40

60

80

1/Q

, m

time, min

Late coarsening:

~ 0.1 t

Coarsening

31

~ 0.1 t 0 50 100 150

0

20

40

60

80

1/Q

, m

time, min

Late coarsening:Siggia, 1979

1adz

Hd

P


PS/SAN20 50/50

Pin2a

PP

~ 0.1 t

Coarsening

32

0 50 100 150

0

20

40

60

80

1/Q

, m

time, min

Late coarsening:Siggia, 1979

1adz

Hd

P


PS/SAN20 50/50

Pin2a

PP

8d Hdt

Coarsening

33

34

Excess free energy localized at the interface.

1 2

2H

Mean Curvature

34

ˆinterfacedU H A dn

int ;ˆ

erfacedU dAdA HAdn

1 2

2H Excess free energy localized at

the interface.

Mean Curvature

35

Mean Curvature DistributionPS/SAN20 50/50 Blend

-2 -1 0 1 2

0.01

0.1

1

10

5 min 10 min 30 min 60 min

PH,

m

H, m-1

[ | / 2 / 2]( )

( ) 1

jj

Hj

j

H

A j H H H H HP H

H A

P H H

36

Mean CurvaturePS/SAN20 50/50 Blend

-4 -2 0 2 4

0.01

0.1

1


Q P

H

H/Q-2 -1 0 1 2

0.01

0.1

1

10


PH,

m

H, m-1

37

-4 -2 0 2 4

0.01

0.1

1


Q P

H

H/Q

-4 -2 0 2 41E-3

0.01

0.1

1


Q P

H

H/Q

Mean Curvature

38

0 50 100 150

0

20

40

60

1/Q

, m

time, min

-4 -2 0 2 4

0.01

0.1

1


Q P

H

H/Q

-4 -2 0 2 41E-3

0.01

0.1

1


Q P

H

H/Q

Mean Curvature & Coarsening

39

2 21 2C

2A

Curvedness:

ˆinterfacedU H A dn

0 60 120 1800

30

60

1/Q

, m

time, min

0.1

0.2

0.3

C, m

-1


40

0 60 120 180

time, min

0.1

0.2

0.3

C, m

-1

C tn

Curvedness:2 2

1 2C2

A


8d Hdt

Pin2a

PP

41

8d Hdt

Pin2a

PP

2 2

~ exp

C 2H K

Hdt

0 60 120 180

time, min

0.1

0.2

0.3

C, m

-1

C tn


Curvedness:2 2

1 2C2

A

42

0 60 120 180

time, min

0.1

0.2

0.3

C, m

-1

C tn

8d Hdt

Pin2a

PP


42 3exp cc c t

~ exp Cdt


43

1c t

Early coarsening:


=

1/Q

, m

0

20

40

60

80FLPS/SAN20

FLPS/SAN30

FLPS/SAN10

0 25 50 75 100 125 150

time, min44

42 3exp cc c t

1c t

Early coarsening:

Early and late coarsening:


=

1/Q

, m

0

20

40

60

80FLPS/SAN20

FLPS/SAN30

FLPS/SAN10

0 25 50 75 100 125 150

time, min45

1 2K

K<0 K>0 K=0, H0 K=0, H=0

Hyperbolic PlanarParabolicElliptic

Gaussian Curvature

46

K<0 K>0 K=0, H0 K=0, H=0

Hyperbolic PlanarParabolicElliptic

-0.4 -0.2 0.0 0.2

1

10

100


PK,

m2

K, m-2

[ | / 2 / 2]( )

jj

Kj

j

A j K K K K KP K

K A

1 2K PS/SAN20 50/50

Gaussian Curvature

47

Sphere Torus Double torus . . . Bicontinuous

. . .

g=0 g=1 g=2 . . . g=

2 (2 2 )Kda g Gauss-Bonnet Theorem:

1 2K

Gaussian Curvature

48

Interface Topology

10 100101

102

103

104

35/65 50/50

g/V

, mm

-3

time, min

-1.7

5 min 10 min 20 min

G=g/V (1/Q)1.7

50 m 50 m50 m

FLPS/SAN20 50/50

49

Interface Topology

10 100

0.1

1

35/65 50/50

G/G

0

time, min

G=g/V (1/Q)1.7

5 min 40 min

FLPS/SAN20 35/65

50

• Visualized and quantify 3D microstructure of cocontinuous blends

•In 50/50 blends we identified two regimes of coarsening:

o Early: linear self‐similar growth of =1/Q (Siggia, 1979).o Late: slowing down due to decrease in H.

• New criterion for pinch‐off based on topological (genus) evolution.

López‐Barrón & Macosko, Langmuir, 2009López‐Barrón & Macosko, Soft Matter, In Preparation

Summary

51

Outline





Batchlor, J. Fluid.Mech., 1970Interface tensor

Onuki, Phys.Rev. A, 1987

Vinckier And Laun, J. Rheol., 2001.

Rheology of 2-phase liquids

• Oldroyd (1953,1955)Dilute emulsions of Newtonian liquids

• Choi‐Schowalter (1975)Semidilute emulsions of Newtonian liquids

• Palierne (1990)Emulsions of viscoelastic components

Droplet‐matrix morphologies

• Doi‐Ohta (1991)

Complex interfacesCocontinuous?

Rheology Modeling

53

13

1ij i j ijq dS n n

V

PDMS/PB

Almusallam et al., 2003

AnisotropySurface tensor:

54

Questions:1‐What is qij of non sheared blends?

|qij |~ 10‐5 m‐1 ~ 0

Anisotropy

55

single strain step

Questions:1‐What is qij of non sheared blends?2‐What is the maximum qij during SAOS experiments?

|qij |~ 10‐4 m‐1

~ 10‐3 N/mqij ~ 0.1 Pa

|qij |~ 10‐5 m‐1 ~ 0

Anisotropy

56

For oscillatory flow:

Experimental fact: max degree of anisotropy qij /Q ~ 3 10‐4

Modeling

Char. Length: =1/Q


57

0ji

ij ij ijj i

vv q px x

0 sin

ij,int

xy

ijq

t

q S t

Modeling


58

0ji

ij ij ijj i

vv q px x

0 sin

ij,int

xy

ijq

t

q S t

Modeling


0.01 0.1 1 10 100

10-1

100

101

102

103

104

105

G''

PS120K/SAN20

shea

r mod

uli,

Pa

, rad/s

G'Components

Blend

59

sin( )ij,int xy

tt q

t

Modeling


0,int 1int

0

( )'

tG t

10t s

60

Modeling


0,int 1int

0

( )'

tG t

Simplification for small amplitudes:

1 tQ

(1)

(2)

≡ Characteristic length

61

0 50 100 150

0

20

40

60

80

100

PS200K-SAN30

PS120K-SAN30

=1/

Q,

m

time, min

PS40K-SAN30

0 50 100 150

0

20

40

60

80

100

PS200K-SAN10

PS120K-SAN10

=1

/Q,

m

time, min

PS40K-SAN10

Characteristic Length, :

= 0.29 ± 0.07 = 1.1 ± 0.2

Q ≡ Interfacial area per unit volume

Coarsening Morphology

62

ªAE

BDF

CG

1 tQ

Coarsening Morphology

63

0.01 0.1 1 10 100

10-1

100

101

102

103

104

105

G''

PS120K/SAN20

shea

r mod

uli,

Pa

, rad/s

G'

Measured at 200 °C with strain =20%

Frequency Sweep

Components

Blend

64

Measured at 200 °C with 0 =20% and = 0.1 rad/s

0 100 200 300

1

10SAN30

SAN20SAN10

PS200K

PS120K

G',

Pa

time, min

PS40K

Time Sweep

65

0 50 100 150

0

20

40

60

PS200-SAN10 PS115-SAN10 PS40-SAN10

G' in

t

time, min0 50 100 150

0

20

40

60


G' in

t

time, min

' ' 'blend comp intG G G

= 0.29 ± 0.07 = 1.1 ± 0.2

Time Sweep

66

0 50 100 150

0

20

40

60


G' in

t

time, min0 50 100 150

0

20

40

60


G' in

t

time, min

0 50 100 150

0.00

0.05

0.10

0.15

PS200K-SAN30 PS120K-SAN30 PS40K-SAN30

Q,

m-1

time, min0 50 100 150

0.0

0.2

0.4

0.6

0.8


Q,

m-1

time, min

Time Sweep

= 0.29 ± 0.07 = 1.1 ± 0.2

67

• Doi‐Ohta (1991) 10int

0

( )' tG t

1 10 1000.1

1

10


G' in

t

time, min1 10 100

1

10

100

PS200-SAN30 PS115-SAN30 PS40K-SAN30

G' in

t

time, min

= 0.29 ± 0.07 = 1.1 ± 0.2

Model vs. Exp. Data

68

• Doi‐Ohta (1991) 10int

0

( )' tG t

1 10 1000.1

1

10


G' in

t

time, min1 10 100

1

10

100

PS200-SAN30 PS115-SAN30 PS40K-SAN30

G' in

t

time, min

= 0.29 ± 0.07 = 1.1 ± 0.2

Model vs. Exp. Data

69

• Identified 2 regimes of elasticity decrease during coarsening,described by

•Developed new method to compute qij from 3D images.

• Proposed simplification to Doi‐Ohta’s model for smalldeformations: ª

Need Improvements

Summary

int' bG t

70

• NSF DMS‐0352143 with J. Lowengrub, UC Irvine

• NSF MRSEC Program (University of Minnesota) under

Awards Number :

– DMR‐0212302

– DMR‐0819885

Funding

71

• Advisor: Chris Macosko

• Committee Members: Tim Lodge, Satish Kumar, Kevin Dorfman

• Research:

– Joel Bell – discussions on cocontinuous blends

– Yutaka Miura – synthesis of fluorescent monomer

– Jerry Sedgewick – confocal microscopes

– Ravi Chityala – 3D reconstruction

– David Morse and Kwanho Chang – block copolymer theory

– Randy Ewoldt ‐ LAOS

• Macosko Group

– Hyunwoo Kim, Luca Martinelli, Aaron Hedegaard, Dawud Tan, Zhengzi Zhu, Suqin Tan, Jing Han,

Kirby Liao, Chunfeng Zhou, Jaesoo Yang, Jie Song, Adam Wohl, Shingo Kobayashi, …

• Undergrads: Kate Dennehy, Yessica Lie

• Friends/Family: Parents, Yeny, Cristobal and Sofia

Acknowledgements

72

Documents

On the Coarsening of Cocontinuous Polymer Blends€¦ · Laser Scanning Confocal Microscopy (LSCM): 3D Imaging 11. Fluorescent‐Dye Monomer (AMMA) Synthesis: FL‐Polystyrene synthesis