Submitted to: Materials Research Society Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: April 8, 1996
Publication Date: N/A
Studies were conducted to evaluate and compare the biodegradation of starch-PHBV blends in several natural ecosystems, such as soil, activated sludge, compost, tropical mangroves and coastal waters. Samples were exposed in these environments and retrieved after a specified period of time and analyzed for degradation. The degradation was assessed by the (a) loss of weight and tensile properties of the composite material, (b) changes in the chemical composition of polymers as indicated by chemical extraction, FTIR, and proton NMR, (c) differences in the average molecular weight distribution of polymers before and after degradation. While starch-PHBV blends degraded in all environments, the rate and extent of degradation varied from environment to environment. Furthermore, degradation of starch was much faster than PHBV and the extent of PHBV degradation was directly correlated with the amount of starch present in the blends. The formulation, processing and mechanisms of biodegradation of starch-PHBV blends will be discussed.