Life Cycle Assessment Of Plycarbonate And Polylactic Acid

Polylactic acid (PLA),polycarbonate (part-petroleum, non-petroleum) and other biodegradable polymers waste can be degraded into water and carbon dioxide in a short period by natural microbial. It solved a series of environmental problems resulting from the contamination of polyethylene (PE) and other traditional non-degradable (degradation time is 100 to 200 years) polymer materials. A large number of studies which have be done are all about how to improve the function and synthesis of the material, however, the environmental impact of the whole life cycle processes of biodegradable materials and various stages and units processes, and different types of biodegradable materials as well as biodegradable materials and traditional plastics difference in the environmental impact are rarely reported.In response to this situation, this paper analyzed three biodegradable ploymers, namely part-petroleum polycarbonate - poly propylene carbonate(PPC), poly lactic acid and non-petroleum polycarbonate (NPC) by life cycle assessment (LCA) method to carried out environmental impact of three biodegradable materials. The main environment impact categories of three kinds of the resin in their life were global warming and acidification. Both of these environment impact accounted for 86.26%, 79.14%, 81.81% of the total environment impact of PPC, PLA, NPC. A detailed analysis for raw data showed that environmental burden was most predominant in the material production stages. The most predominant environmental burden in the production stages and their environmental impact categories were as follows: first of all, the propylene oxide production stage had the most predominant environmental burden in the production stages of PPC, whose environmental impact categories was global warming ; secondly, the lactic acid production stage had the most predominant environmental burden in the production stages of PLA, whose environmental impact categories was global warming; thirdly, the furfural and furan methyl ether production stages had the most predominant environmental burden in the production stages of NPC, whose environmental impact categories was global warming.Based on the research above, the three kinds of biodegradable plastics and traditional plastics polyethylene (PE) of the environmental impact were compared. The results showed that human toxicity and acidification had the most contribution in PLA production, photochemical oxidation and abiotic depletion had the most contribution in PE production, global warming had the most contribution in PPC production, and NPC in various environmental impacts were minimum. Among the four polymers, the potential burden of PLA was the severest, which was 24.89% more then PE, second was PPC that had 13.79% more environmental burden than PE, the environmental burden of NPC was minimum for it had been 34.18% compared with PE.Finally, the paper the analyzes production process of PLA and PPC which had a larger environmental impact, and took some suggestions to improve the environmental impact of them, and the environmental impact of the two materials were discussed potential for improvement in order to improve the environmental performance of the two materials .