Thermal Degradation Kinetics of Biopolymers and their Composites: Estimation of Appropriate Kinetic Parameter

Abstract

Renewable resource based polymers are biodegradable, biocompatible and eco-friendly in nature. Starch, Cellulose, Chitin, Chitosan, Poly (3-hydroxybutyrate) (PHB), Poly (lactic acid) (PLA) and poly (ε- caprolactone) (PCL) are used in biomedical field and for food packaging purposes. Due to limited thermal stability, these polymers undergo significant degradation when exposed for long time during industrial processing. Understanding of thermal behaviour of these polymers and their composites need to be investigated towards their applications. In the current research work, thermal degradation kinetics of pure PLA, PHB, PCL and chitosan along with various bio-fillers and inorganic fillers are studied. Thermal gravimetric analysis (TGA) data reported in literature for non-isothermal experiments were used to determine the thermal degradation behaviour and associated kinetics. Efforts were made on understanding the applicability of various models. Reconstruction of the conversion profiles for different thermal history were performed and compared with experimental data. A choice of a model for a specific material was investigated based on root mean square (RMS) values.