Research on synthesis and thermal properties of poly(ethylene terephthalate) sulfonate group containing ionomer

In order to solve the poor nucleation ability and slow crystallization rate of polyethylene terephthalate (PET), we propose a new strategy to prepare PET with self-nucleation ability based on the mechanism of mutual attraction of ions. In this study, a hydroxyl-terminated sulfonate monomer, sulfonated 1,4-butanediol (SBDO) without rigid structure was synthesized as nucleating agent functionalized PET third monomer, and then PET ionomers (PETi) were prepared through melt polycondensation with different contents of SBDO. The half-crystallization time of PETi was sharply decreased in contrast with pure PET and the crystallization temperature was significantly increased from 182.6°C to 210.8°C for PETi1. Due to the high nucleation efficiency of SBDO, the crystallization temperature of PET was significantly increased, avoiding the excessive addition of traditional nucleating agents to deteriorate the mechanical properties of PET. The increased nucleation efficiency was contributed to the aggregation of SBDO induced by the ionic interactions.