Biodegradable Plastics Based on Starch

Abstract

The predominant persistence of plastic materials based on petroleum in the environment has resulted in a wide range of pollution and waste disposal problems. Consequently, environmentally degradable plastic materials based on annually renewable biological products, such as starch, are considered by many people as a solution to these problems and, since the 1970's, the research and development of plastics based on starch are intensively conducted on a world scale . These biodegradable plastics are expected to replace conventional plastics currently used for many singleuse items such as garbage bags, shopping bags, diaper linings, bottles, sanitary applicators, fast food service items and so on. But the rate and extent of biodegradation of these starch-based plastics in various environments have not been clarified. Besides, the costs are much higher than conventional petroleum-based plastics and are resisted by consumers . However, we expect that our continued efforts may provide starch-based biodegradable plastics that provide comparable physical properties and resonable costs in comparison with conventional petroleum-based plastics. In this paper, we reviewed briefly the present conditions of starch-based biodegradable plastics about the following subjects : the standard definitions of biodegradability and standard regulations, the predominant situations of starch as a replacer for the conventional plastics, the physical and chemical modifications of starch for use in biodegradable plastics, and starch-based biodegradable plastics currently available on the market .