An effective nucleating agent for isotactic polypropylene (iPP): Zinc bis- (nadic anhydride) double-decker silsesquioxanes

The zinc bicyclo [2.2.1]-heptane-2, 3-dicarboxylate-double-decker silsesquioxanes (Zn2(DDSQ-ND)) was firstly synthesized and the crystallization behavior of isotactic polypropylene (iPP) filled with different amount of Zn2(DDSQ-ND) (0?1 wt %) was investigated in detail. With the addition of Zn2(DDSQ-ND), the crystallization temperature enhanced significantly, indicating that it acted novel and effective nucleating agent in the iPP system. The morphology of spherulites, nucleation density, and the crystal structure of the samples were characterized using POM and WAXD. Besides, ultra-fast scanning calorimetry (FSC) was employed to study the effects of Zn2(DDSQ-ND) on the non-isothermal and isothermal crystallization behaviors of the sample iPP/Zn2(DDSQND) under the high cooling rates and wide crystallization temperature ranges, as well as the cold crystallization and recrystallization behavior during the heating process. The data suggested that Zn2(DDSQ-ND) accelerated the formation of ?-phase iPP and acted as a novel ?-nucleating agent in the iPP system.

Automated summary

The study synthesized zinc bicyclo [2.2.1]-heptane-2, 3-dicarboxylate-double-decker silsesquioxanes (Zn2(DDSQ-ND)) for the first time and investigated its effect as a novel and effective nucleating agent in the crystallization behavior of isotactic polypropylene (iPP). The results showed that Zn2(DDSQ-ND) accelerated the formation of ?-phase iPP and acted as a novel ?-nucleating agent in the iPP system.