Poly(ethylene terephthalate-co-isophthalate) synthesized via a Sb/Al bimetallic compound catalyst: the effect of the end groups on the properties of polyester

Herein, poly(ethylene terephthalate-co-isophthalate) (PETI) was synthesized via an ethylene glycol stibium/gamma-AlOOH composite catalyst and a study was carried out on the structural changes of the end groups of poly(ethylene terephthalate-co-isophthalate) (PETI). Based on this study, the effect of the structural changes of these end groups on the crystallization and optical properties of polyester has been discussed. Moreover, it was found that after the catalytic reaction, the gamma-AlOOH and the carboxyl end groups of PETI generated terminal carboxyl aluminum coordination compounds. The composite catalyst generated alkoxy aluminum and alkoxy stibium. The strong nucleating ability of these new end group structures changed the crystallization properties of the polyester. Moreover, the optical properties of the polyester were affected and as a result, a 90.46% transmittance for PETI was observed.