1

Deepak Venkatraman, Jed Randall

NatureWorks LLC www.natureworksllc.com

ITR 2012 Presentation

Hydrolytic stability of Ingeo PLA

February 2012

Equilibrium swell concentration of water in high molecular weight Ingeo PLA in humid environments

01,0002,000

3,0004,0005,0006,0007,0008,000

9,00010,00011,00012,00013,000

14,00015,00016,000

0 10 20 30 40 50 60 70 80 90 100

Humidity (% RH)

Moi

stur

e C

onte

nt (p

pm)

Low HighTypical

57 (%)106.6(%)8.40)( RHxRHppmWater −+=

Confidential

Drying Curve for Equilibrium Moisture Level Polylactide Pellets,Dryer setup: 0.25 cfm/lb pellets; Dewpoint = -40 C

0

250

500

750

1000

1250

1500

1750

2000

2250

2500

2750

0 1 2 3 4 5 6 7 8 9 10 11 12 13

Drying Time, Hrs

Pelle

t Moi

stur

e, p

pm

100°C, Crystalline PLA

80°C, Crystalline PLA

60°C, Crystalline PLA

50°C, Amorphous PLA

Drying Ingeo Resin using Desiccant Drier

Confidential

Water Pickup of Crystalline Ingeo Pellets

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

0.1 1 10 100

Time (hrs)

Wat

er C

onte

nt (p

pm)

50% RH80% RH

< 1h at high moisture: too high for stable

extrusion

Moisture Gain of Ingeo™ Biopolymers

Viscosity Stability of Ingeo in the Presence of Water at Various Temperatures

Viscosity Stability of Ingeo with < 100 ppm Water (constant shear rate of 10 sec-1)

1000

10000

100000

0 300 600 900 1200 1500 1800

Time (seconds)

Visc

osity

(pa-

sec)

180 C 210 C 240 C

-4% -5%

-5.5%

-15%

-5%

-4.5%

- 10%

-4.5

-24%

-7%

-5%

-20%

Viscosity Stability of Ingeo with 850 ppm of Water(constant shear rate of 10 sec-1)

100

1000

10000

100000

0 300 600 900 1200 1500 1800

Time (seconds)

Visc

osity

(Pa-

sec)

180 C 210 C 240 C

- 11%- 23%

- 43%

- 37%

- 35%

- 17%

- 27%

- 21%

- 43%

- 49%

- 29%

- 43%

30 minutes

Moisture effects on Processing Ingeo extrusion → Lower viscosity Melt strength → Water like extrudate (sag) Melt pressure → Low pressure at die Crystallinity → Higher rate of crystallinity Casting → Poor web stability Molding → Increased brittleness and potential

flash

Molecular weight loss, for amorphous 10% D PLA stored at aggressive temperature and humidity

1000

10000

100000

1000000

0 20 40 60 80 100 120 140 160 180 200

time (days)

Mw

by

GPC

40 deg C, 50% RH

40 deg C, 80% RH

60 deg C, 80% RH

80 deg C, 20% RH

80 deg C, 80% RH

Below Tg

Above Tg

Background- Ingeo PLA hydrolysis • Under high humidity & temperature, PLA can undergo

hydrolysis of ester-bonds leading to rapid Mw degradation

• Hydrolysis of ester bonds are random along the PLA chain and can be catalyzed by the acid end-group General hydrolysis scheme

HOO

OOH

CH3

O CH3

O CH3

O

H2O

H2O

HOO

OOH

CH3

O CH3

O CH3

O

OOH

CH3

O

PLA

OOH

CH3

O

PLA

HOOH

CH3

O

HOO

OH

CH3

O CH3

O

Background contd., • Reagents can be used to cap acid end-group and slow

1st hydrolysis event • This 1st event generates an acid that catalyzes further

hydrolysis

HOO

OOH

CH3

O CH3

O CH3

O

End-CappingReagent

R-

H2O

HOO

OO-R

CH3

O CH3

O CH3

O

HOO-R

CH3

O

HOO

OH

CH3

O CH3

O

Slow

H2O

HOO

OO-R

CH3

O CH3

O CH3

O

HOO

OH

CH3

O CH3

O

HOO-R

CH3

O

HOO

OH

CH3

O CH3

O

Fast

2

Background contd., • Excess of end-cap agent could sequester newly formed

acid groups, minimizing hydrolysis rate

BioAdimide 500XT hydrolytic stabilizer for Ingeo PLA

Material Commercial name Supplier Chemical

Formula weight fraction

25°C density [g/ml]

Matrix Ingeo™ 3001D NatureWorks LLC PLA 0.711 1.24

Impact Modifier Biostrength® 150 Arkema Inc. Proprietary core-shell copolymer 0.100 1.00

Crystal accelerant Plasthall® DOA The HallStar Company Dioctyl adipate 0.090 0.98

Reinforcing Agent ULTRATALC® 609 Specialty Minerals Inc. <0.9 μm particle 3MgO·4SiO2·H2O 0.090 2.80

Nucleating Agent LAK-301 Takemoto Oil & Fat Co., LTD Aromatic Sulfonate Derivative 0.009 1.00

Ingeo™ 3801X components

GPC Mw vs storage time- Ingeo 3801X IM bars, 80%RH

%Loading Impact on MW retention

0.5 2x1 5-7x2 >7x

40deg C 60deg C

70deg C

GPC Mw vs storage time- Ingeo 3001D IM bars, 80%RH

40deg C

70deg C

60deg C

% Loading Impact on Mw retention

0.50 2x1 8x2 ~10%Mw loss

Physical testing data- 3801X IM bars

Physical testing data- 3001D IM bars

BioAdimide 500XT hydrolytic stabilizer for Ingeo PLA fiber

D. Venkatraman C. Kamann

•The black dash-line indicates 50% Mw loss for the control (~17days). Samples were rated against this value for relative time retention •Some Mw increase was noted following extrusion (t=0) with the addition of BioAdimide •Mw retention is very sensitive to BioAdimide loading

Ingeo Fiber 60°C/80%RH storage study GPC Mw vs storage time: 3001D oriented fiber

Additive loading (wt%)

Approx impact on Mw retention

0.25 1.6x0.5 2x0.6 2x0.8 3.3x1 5x

2 8x

Ingeo Fiber 60°C/80%RH storage study Fiber tenacity vs storage time: 3001D oriented fiber

•The black dash-line indicates 50% tenacity loss for the control; the other samples were rated against this value for relative time retention •Significant improvement in tenacity and physical property retention is seen at loadings of 0.5wt% BioAdimide and higher

Additive loading (wt%)

Approx impact on phys prop retention

0.25 1.3x

0.5 2x

0.6 2x

0.8 2x

1 5.5x

2 >10x

Conclusions

• Mw loss during typical extrusion can be easily controlled through drying

• Moisture equilibrium and kinetics of gain and loss are well understood

• Hydrolysis of Ingeo PLA can be modified and controlled through the addition of polycarbodiimide – Limits acid catalysis – Effective at storage conditions – Increased dosing provides for longer MW protection

Acknowledgements-

• Frank Diodato • Chad Kamann • Karl Ludescher • Jed Randall • Joe Schroeder