Determination of crystallization parameters and occurrence of trans-reaction in a ternary polymer blend system

Differential scanning calorimetry (DSC) results under non-isothermal cooling conditions of a blend consisting of polytrimethylene terephthalate (PTT)/polybutylene terephthalate (PBT)/and polycarbonate (PC) in the ratio 25:25:50 wt% are reported. Kissinger and Matusita models were used to evaluate the kinetic parameters for the crystallization process for the neat polyesters and the blend. Probable growth mechanisms which occur during the transformation from amorphous to crystalline state are discussed. The blend system comprising of semicrystallizable polyesters and an amorphous polycarbonate was characterized for possible trans-reaction occurring in the system using differential scanning calorimeter, proton nuclear magnetic resonance (1H NMR), and Fourier transform infrared spectroscopy (FT-IR) analysis. DSC analysis of the blend indicated that it is an immiscible system. 1H NMR and FT-IR analysis indicate that no chemical trans-reaction is found to have occurred between these three polymers. Based on these results it can be justified that transesterification was not a necessary condition for miscibility in PTT/PBT/PC blend.