BIODEGRADABILITY OF POLYMERS AND FIBERS - A REVIEW OF THE LITERATURE

This review deals with the biodegradability of fibers and polymers, including cellulose, polyolefins, polyesters, polyamides, polyurethanes, polystyrene, polyvinyl chloride, polyvinyl alcohol, polyvinyl acetate, and polyacrylates. Conclusions are drawn about physical and chemical properties important for imparting biodegradability to polymers. For a polymer to be biodegraded, enzymes secreted by microorganisms must have access to the surface of the polymer at a point where they can initiate biodegradation. Characteristics that promote biodegradability include hydrophilic properties, amorphous structure, flexible chains, and low molecular weight. The critical chemical groups include chemical linkages in the polymer backbone and the structure of the end groups and pendant groups, if present. Aliphatic polyesters, polyurethanes made from polyesters, many polyamides, polyvinyl alcohol, polyvinyl acetate, polyacrylates, and most naturally occurring polymers are biodegradable, whereas polyolefins, polyvinyl chloride, polystyrene, aromatic polyesters, and polyurethanes made from polyethers are generally resistant to microdegradation.