Biodegradable Plastics

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Biodegradable Plastics

• Marina Dickens
• November 10th, 2004

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Plastics

• Make it possible
• Almost indestructible and impermeable
• PET (polyethylene terephthalate)
• Alternatives
• Starch
• Polyester
• Food waste

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Poly L-Lactic Acid (PLA)

• Uses packaging, fibers, carpeting, noted
  resistance to microbes
• MP 175C
• Production
• Totally synthetic
• Recycled food waste

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Propionic Acid Fermentation
Propionibacterium freundenreichii
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Lactic Acid Fermentation
Glucoamylase Lactobacillus rhamnosus, Water
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Purification of L-Lactic Acid
waste
Butyl lactate
Water, heat

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Distillation-Crystallization
catalyst
catalyst
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Biodegradability Initial studies

• Chemical hydrolysis
• Enzymatic ester bond cleavage by
• proteinases and lipases
• PLA after 45 days 30 biodegradation

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Benefits

• Less landfill material
• Less methane release from food waste
  decomposition
• Reduction from 270 metric tons fossil fuel
• Compensate for higher energy use (39.5 v 27
  MJ/kg)
• Reduction in fossil fuel-derived CO2 (burning)

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References

• Sakai, K. et al. Making Plastics from Garbage A
  Novel Process for Poly-L-Lactate Productino from
  Municipal Food Waste. Journal of Industrial
  Ecology. V 7 No 3-4 p 63-74 2004.
• Stevens, E.S. What Makes Green Plastics Green?
  BioCycle. V 44 no 3 p 24-27 March 2003.
• Wang, Xiu-Li et al. Properties of Starch Blends
  with Biodegradable Polymers. Journal of
  Macromolecular Science. V C43 No 3 pp 385-409
  2003.