Effect of calcium pimelate on crystallization kinetics of polyphenylene sulfide

The use of nucleating agents (NAs) to accelerate semicrystalline polymers crystallization is a widely recognized technique during processing. However, the commercially available NA for poly(phenylene sulfide) (PPS) has been rather limited. In this work, it is found that calcium pimelate (CaPim), a commercial nucleating agent for isotactic polypropylene, could also accelerate the crystallization process of PPS. The influence of CaPim addition on the crystallization behaviors of PPS was investigated under non-isothermal and isothermal condition. Upon the addition of 0.3 wt% CaPim, the crystallization peak temperature and the onset crystallization temperature increases by 5.3 and 8.4 degrees C at 10 degrees C/min cooling rate, and the half-time of crystallization reduces 51% at crystallization temperature of 272 degrees C. Polarized optical observation revealed a substantial enhancement in nucleation due to the presence of CaPim. Avrami equation analysis suggested that the nucleating agent significantly increased the crystallization rate constant without affecting the growth dimension. Moreover, Lauritzen-Hoffman theory analysis indicateed that the addition of CaPim lowers the nucleation energy barrier, contributing to its high-nucleation efficiency. These findings demonstrate that calcium pimelate holds promise as an effective nucleating agent for PPS.