Thermoplastic Starch (TPS) Based Bio-disintegrable Polymers - Combination of Modified Potato Starch with Polyolefins

Research is striving for achieving a target of fully biodegradable polymer product and in that direction an effort has been made and presented in this paper. The combination of thermoplastic starch based natural polymers and typical in use synthetic polymers has been done to develop biodegradable polymeric materials. The first and foremost use of these materials could be in industry for packaging applications. The materials developed during study are Biodegradable plastics with varying characteristics. Different types of biodegradable polymer compositions were prepared using modified potato starch with different poly olefins through melt processing technique on laboratory scale. Efforts have been made to utilize various modifiers available as on date like Glycerol, Sorbitol and Urea introduce thermoplastic properties in starch then these processed thermoplastic starches were melt processed in Haake Rheocord with polyolefins like LDPE, LLDPE, HDPE and PP. The system thus prepared has been characterized through methods available as on date. Water Absorption studies were also conducted on samples thus prepared and biodegradation through soil burial method was performed on laboratory scale. Observations were that modification of starch leads to an increase in the thermoplastic character in sample blends thus prepared along-with increased thermal stability in starch. During comparison study of different modifiers it was observed that GTPS blend gives better mechanical, thermal and chemical properties than STPS and UTPS blends. During Biodegradation study the observations were that biodegradability got enhanced with the increased % of TPS in blends. Since, starch concentration associates with the degradation through microorganism, higher concentration of TPS causes considerable compatibility between bacterial phase and chemical strength of plastic. Whereas, starch being less crystalline and hydrophilic in nature compared to LDPE, is more prone to microbial attack