Research of the influence factors on transesterification reaction degree in PC/PBT blends

PC/PBT blends have excellent comprehensive properties and are widely used in the market. It's inevitable that transesterification reaction will take place in the melting process for this kind of blends, and this reaction has decisive effects on the blend properties, in this paper, the effects of resin ratio of PC to PBT, resin viscosity and processing technology on the transesterification reaction degree were studied. Considering that the reaction occurred at the phase interface of PC and PBT, with the combination of the phase morphology and crystallization behavior of PBT phase under different resin ratios, the correlation between phase morphology and transesterification degree was established. From the perspective of PBT phase, the lower its ratio is, the smaller its phase size is, the worse its crystallinity is, and the greater the transesterification degree, besides, the lower PBT resin viscosity, the higher the transesterification degree. Moreover, through the research on processing technology, the higher the extruder speed, the higher the transesterification degree. Those studies will provide direct guidance for further research on the influence factors of the transesterification degree and the actual processing of the corresponding products.