The crystallization behaviors of copolymeric flame‐retardant poly(ethylene terephthalate) with organophosphorus

The crystallization behaviors of copolymeric flame-retardant poly(ethylene terephthalate) (PET) with organophosphorus were studied using differential scanning calorimetry (DSC). The results indicated that the degree of tacticity of molecular chain of PET declined due to the presence of organophosphorus which had an important impact on isothermal and nonisothermal crystallization behaviors apparently. In the process of isothermal crystallization, the more organophosphorus the samples contained, the faster the samples crystallized and it resulted from the special structure of PET copolymer with organophosphorus in it. The equilibrium melting temperature of PET decreased from 284.87 to 260.72°C as the content of organophosphorus increased from 0 to 0.96 wt%, whereas in the process of nonisothermal crystallization, the Avrami exponent n decreased with the growth of the content of organophosphorus, and the addition of organophosphorus made the nucleation mechanism and the growing geometry less complicated. POLYM. COMPOS., 34:867–876, 2013. © 2013 Society of Plastics Engineers