EFFECT OF BLENDING ON THE CRYSTALLIZATION BEHAVIOR OF PET

The crystallization of poly(ethylene terephthalate) (PET) in its blends with other thermoplastics such as poly(phenylene sulfide) (PPS), high-density polyethylene (HDPE), poly (methyl methacrylate) (PMMA), aromatic polyamide, and a co-polyester is reported. The nonisothermal crystallization and melting behavior of PET in its blends has been discussed. Because of differences between the melting/softening points of these polymers and the melting point of PET, the crystallization of PET takes place in the presence of solidified PPS in PET/PPS blends and in presence of the molten phase of the second component in the remaining blends. The observed changes in the melting and crystallization behavior are explained on the basis of the effect of the physical state of the second component. The results of the isothermal crystallization studies are consistent with these studies. The changes in the overall crystallization rate could be further explained in terms of the nucleation and growth processes occurring during the crystallization of PET using the isothermal crystallization data.