Biopolymer micro and nanocomposites: modification of interphasesDr Katherine Dean, S. Petinakis, C. Way, A. Scully, M. Do, P. Sangwan, L. Yu, X. Zhang, DY. Wu,

E. Palombo, G. Edward CSIRO Materials Science and Engineering, Gate 5 Normanby Rd, Clayton, 3168, Australia, Swinburne University

Melbourne Australia, Monash University Melbourne Australia

Rome 16th April 2009

CSIRO (Commonwealth Scientific and Industrial Research Organisation) Australia

• Australia’s national research organisation (similar to CNRS in some respects)

• multidisciplinary (materials - polymer, ceramics, metals, plant industries, entomology, sustainable ecosystems, bushfire research)

• Sites all over Australia and around 6000 staff

• Our site is located in Melbourne, Victoria• Dedicated program to sustainable

polymer materials with around 50 research scientists engineers, PhD and postdocs

Polymer classes

• Biodegradable and renewable• From a renewable resource (corn, wheat, soy etc)• 100% biodegradable and compostable

• Biodegradable and non-renewable• From a petrochemical resource• 100% biodegradable and compostable

CSIRO polymer processing and design facilities

• Extrusion• Single & twin screws, co-extrusion,

foaming, sheet dies etc• Screw design• Reactive extrusion (liquid injection and

multi gravimetric feeding)

• Thermoforming• Scale-up from technologies developed in

the laboratory

• Film Blowing• Fibre Spinning • Characterization

• mechanical and thermal properties, x-ray diffraction

• permeability• Transmission electron microscopy • Scanning electron microscopy

State-of-the-art biodegradation facilities (commissioned in 2007)

• Used for commercial and strategic science projects

• Fully automated matrix of bioreactors

• Testing to Australian and European Standard AS 4736-2006 and EN 13432

Respirometer schematic

Compressed Air

Water

Humidifer(90%RH,23C)

Flowmeter(0-1L/min)

Waterbath + Bioreactor(58C, dark) (3L, dif plate)

Condens. glassware

ElectronicSolenoid

1

156 lines

Flowmeter (0-1L/min)

IR 02/CO2

(02<22% CO2<8%)

Computer + Labview(datalogger) (controller)

Hardware interface (signals in + controls

out)

T H T F O2CO2I/O

Biopolymer structures

O CH2 C CH2 C

O

N O

O

n

m

polybutylene succinate adipate (PBSA)

Starch (amylose –linear and amylopectin –branched)

Poly(lactic acid) (PLA)

O

OO

O

O

O

O

HO OH

H

OHHOH

H

OH

HOH

HO

H

H

H

HO H

OH

H

OH

H

OH

H

HO

H

H

HOH

O

H

HH

H

1

1

1

O

OHH

HOH

H

OH

H

O

O

OH

HOH OH

H

O

O

OHH

HOH OH

H

O

O

O

OHH

HOH OH

H

O

O

OH

H

HO

HHO

H

O

OO

OH

H

HO

HH

HO

H

H

H

H

H

H

H

H

H

H

H

HOO

OOH

CH3

O CH3

O CH3

O

n

Biopolymer nanocomposites Dean, Yu, Wu Comp. Sci. Tech 67(3-4) 413-421 2007 Dean, Do, Petinakis, Yu Comp. Sci. Tech. 68(6) 1453-1462 2008

• Using techniques which do not involve the use of high toxicity chemicals or agents

• strong ion dipole interactions and edge hydroxy interactions between starch and montmorillonite (MMT) clay

• Interruption of recrystallization by MMT process increasing shelf-life of material

Na+

Na+Na+

OH H

Na+

OHH

Detail of possible interactions between clay platelets, water and poly(vinyl alcohol)

Na+

Na+Na+

OH H

Na+

OHH

Na+

Na+Na+

Na+

CH2

CHO

CH2CH

O

O

CH3

H

n

n

O

O

CH3

CH2

CHO

CH2H

n

n

O

H

HOH

H

17Å

9.8Å*

*Up to 12.77Å depending on the level of hydration

Biopolymer nanocompositesDean,K., Pas,S., Yu,L., Ammala,A., Hill,A., and Wu,D.Y Accepted J Applied Polymer Sci (2009).

PBSA: 5wt% Somasif MEE

PBSA:5wt% Somasif MAE

PBSA:5wt% Somasif MTE

PBSA: 5wt%unmodified clay

Tortuous path

60% reduction in oxygen permeability

Bio-polymer nanocomposites - improvement in tensile modulus

0

100

200

300

400

500

600

700

800

900

1000

0 1 2 5

clay (weight %)

Ten

sile

Mo

du

lus

(MP

a)

baseline PBSA (no Na-FHT)

neat Na-FHT

MEE modified Na-FHT

MAE modified Na-FHT

MTE modified Na-FHT

Biopolymer micro-composites compatibilising matrix and fibre Petinakis, Yu, Edward, Dean, Liu, Scully; submitted to Journal of Polymers and the

Environment (2009).

PLA

wood-flour

Matrix/particle interface PLA

wood-flour

Matrix/particle interface

compatibiliserCellulose OH O C N R

Cellulose O C

O

RNH

Biopolymer micro-composites compatibilising and biodegradation Way, Dean Wu et al publications planned for 2009

• Maple treated with• Glycidyloxy-propyl-trimethoxysilane (5%w/wt fibre)

• Hydrolysed silanol groups forms bonds with the OH-maple or PLA

• Acetic anhydride• Replace OH groups on maple to acetyl and make more

hydrophobic (dispersion, stability, interface)

Biodegradation in aerobic compost

• ISO AS 14855 / ASTM D5338

(samples in compost at 58C, biodegradation via CO2 evolution)

CO2 Evolution

0

20

40

60

80

100

0 10 20 30 40 50 60

Time (Days)

Cu

mu

lati

ve C

O2

(mL

/ves

sel)

Compost Sample + Compost

t

contentgasCOrateflowgastimeCO0 22 )( 100

)(

)()(

2

,22

T

MEANBTT COlTheoretica

COCODeg

CO2 Evolution

0

20

40

60

80

100

0 10 20 30 40 50 60

Time (Days)

Bio

de

gra

da

tio

n (

%)

Sample

3321

,TTT

MEANT

DegDegDegDeg

Lag

Degradation

Plateau

Degradation Traces

0

10

20

30

40

50

60

70

80

90

0 10 20 30 40 50 60 70 80 90

Time (Days)

Deg

rad

atio

n (

%, M

ean

)

Cellulose Powder neat 30% WPC glycidyloxy-silane 30% WPC acetylated 30% WPC

• Biodegradation (compost)

Biopolymer micro-composites compatibilising and biodegradation Way, Dean Wu et al unpublished work 2009

Reduced time to onset of biodegradation

Greater % degradation

Sample Day 0 Day 14 Day 28 Day 41 Day 56

Neat

30% WPC

Glycidyloxy silane

30% WPC

Acetylated 30% WPC

Biopolymer micro-composites compatibilising and biodegradation Way, Dean Wu et al unpublished work

Conclusions

• Composites, nanocomposites and blends of biodegradable polymers have been prepared and studied.

• range of chemical and physical interfacial modification methods.

• superior improvements in a range of properties:•modulus

•tensile strength

•oxygen barrier

•thermal properties.

• Increased interest from industry in this field• Future work – biomimetics, utilising synchrotron science,

developing high performance bio-based materials

Thank You

CSIRO Materials Science and Engineering

Name Katherine Dean

Title Research Scientist

Biopolymer Composites Stream Leader

Phone ( +61 3 9545 2686)

Email katherine.dean@csiro.au

Contact CSIROPhone 1300 363 400

+61 3 9545 2176

Email enquiries@csiro.au

Web www.csiro.au

CSIRO Materials Science and Engineering

Name Stuart Bateman

Position Research Scientist

Sustainable Polymeric Materials Theme Leader

Phone ( +61 3 9252 6128)

Email stuart.bateman@csiro.au

CSIRO Materials Science and Engineering

Name Phil Casey

Title Designed Polymer Interfaces Leader

Phone ( +61 3 9545 2684)

Email phil.casey@csiro.au