Thermal decomposition kinetics of tricomponent polyester/polycarbonate systems

The current work seeks to develop a novel polymeric blend containing polycarbonate(PC)/poly(trimethylene-terephthalate)(PTT)/poly(butylene- terephthalate)(PBT), (50: 25:25, weight/weight percent). This has been prepared using a single screw extruder. The thermal degradation kinetics of the blend and neat polymers have been investigated by means of a Theromogravimetric analyzer (TGA) machine. Theromogravimetric analysis of the neat polymers and the blend was carried out at 5, 10, 15, and 20°C/min under Nitrogen and air atmosphere. Two analytical models, namely Kissinger and Ozawa were used to estimate the degradation kinetic parameters (Activation energy, E and pre-exponential factor, A). The neat polymers were found to be more thermally stable under nitrogen than under air. The solid state decomposition was found to follow a phase boundary controlled mechanism. Possibility of transexchange reactions during melt blending was also analyzed using TGA studies. Residual char of blends of different compositions were also used as an indicator to determine possible exchange reactions