Jake Behrens

1. National Science Foundation
Industry & University Cooperative Research Center
Biocontainer Material
Properties & Utility
Presented by: Jake Behrens

2. Overview
• Materials
– Matrices
– Fillers
– Plasticizer
• Formulations
• Processing
– Extrusion
– Injection Molding
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• Difficulties
• Results
– Tensile
– Crush
– Colorant

3. Polymer Matrices
• Must be:
– Renewable/bio-based
– Preferably degradable
– Attainable
• PLA
• PHA
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4. PLA - Overview
• Post-process recycled PLA
– NatureWorks 3001D
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5. PHA
• Metabolix
Mirel PHA
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*Image courtesy of Hydal BioTech

6. Matrix Comparison
PLA
• Hydrolysis
• Cost competitive
• Can become brittle
• Compostable
• Ease of processing
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PHA
• Water insoluble
• Expensive/hard to obtain
• More durable
• Faster degradation
• Long crystallization time

7. Filler Materials
• Must be:
– Renewable/Bio-based
– Increase degradation or strength properties
– Easily attainable
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8. Filler Materials
• Soy Polymer
– Developed at ISU
– Pre-extruded
– High nutrient content
• Lignin
– Readily available
– Many side chemistries
• Varies by feedstock
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9. Filler Materials
• DDGS (Distillers Grains)
– Abundant
– Inexpensive
– Large particle size
• BioRes
– Modified DDGS (Laurel Biocomposites)
– Superior blending to DDGS
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10. Plasticizer
• Polyethylene glycol
– PEG 8000 @ 10%
• Decrease process temps
– Less denaturing of filler (SPA, BioRes)
• Increase flow and process-ability
• Co-product of biodiesel production
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11. Formulations
• PHA-DDGS (80/20)
• PLA-Lignin (90/10)
• PLA-Soy (60/40)
• PLA-BioRes (80/20)
• PLA-Soy-BioRes (50/30/20)
• PLA-Soy-BioRes (55/35/10)
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12. Processing - Extrusion
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13. Processing – Injection Molding
• Arburg 470C
– 165 ton clamping force
– 1.5” screw, 8.2 oz shot
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• Keep residence time short
• Fillers can impede flow

14. NPE
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15. Difficulties Overcome
• Lack of shear thinning
• High injection pressure
• PLA + Water
• Residence times
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16. Results – Tensile Tests
• Instron load frame
– ASTM D638 tensile test
– Type I dogbone
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17. Results – Crush Tests
• Instron load frame
– Compressive mode
– Two steel plates compress pots
– Horizontal (left) and vertical (right)
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18. Results – Effect of Colorant
• Effect of 1% petroleum-
based green colorant
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19. Conclusions
• Avoid moisture
• Decrease process temps (plasticizer)
• Colorant aids appearance & strength
• Filler content & strength inversely proportional
– Affects growth
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