Biodegradation of Polymer Films in Marine and Soil Environments

The emergence of biodegradable plastics has necessitated the development of standard methods to determine biodegradation rates in various environments. Standardized accelerated marine and soil laboratory biodegradation test systems were developed in which comparative polymer biodegradation rates could be determined by quantifying and plotting the weight loss/surface area of each sample over time and determining the maximum slopes of the curves generated. The results indicate that, in general and depending on the environment, biodegradation rates for unblended polymers were: polyhydroxybutyrate-co-valerate > cellophane > chitosan > polycaprolactone. Results from blends are more difficult to interpret since different biodegradation rates of the component polymers and leaching of plasticizers and additives can impact the data.