Preparation and characterization of thermoplastic starch at pilot plant scale

MARÍA PAULA GUARÁS; LEANDRO LUDUEÑA; VERA ALVAREZ

Buenos Aires

Conferencia; VI International conference on science and technology of composite materials, COMAT 2015; 2015

Conventional polymers derived from fossil fuels are not only non-renewable and finite resources, but also cause problems in processing post-consumer because they are largely inert to microbial attack. The use of polymers able to be degraded by the action of microorganisms and/or enzymes without causing harmful effects is a strategy in waste management. Starch is an abundant and low cost natural biopolymer obtained from renewable resources. However, the structure of native starch must be modified, since starch degradation starts at a temperature lower than its melting point. For this reason native starch cannot be processed by conventional plastics technology without any modification. This modification is performed by the breakdown of the starch granule when it is processed in the presence of a specific amount of plasticizer, at a given extrusion conditions. In this work, two formulations of thermoplastic starch optimized in previous studies were selected. The materials were blended in a twin-screw extruder at different conditions of temperature and plasticizer content. After the extrusion, the material was pelletized and films were prepared by compression molding for further characterization. The thermal and mechanical properties and water absorption of the obtained films were characterized.