Non-isothermal crystallization kinetics of organic montmorillonite/SiO2 aerogel/PET composites

Purpose Crystallization kinetics is a key factor that controls the crystallization process of polymers and influences the crystallinity and morphology of polymers. This study aims to explore the effects of functional filler SiO 2 aerogel and co-modified filler organic montmorillonite (OMMT) on the crystallization process of polyester polyethylene terephthalate (PET). In this study, the nonisothermal crystallization kinetics of OMMT/SiO 2 aerogel/PET composites were studied by Jeziorny method. Design/methodology/approach The catalyst (Sb 2 O 3 ), OMMT and SiO 2 aerogel were uniformly dispersed in ethylene glycol (EG). Then, the mixture and terephthalic acid (PTA) were put into a semicontinuous polyester synthesis reactor, and the SiO 2 aerogel/PET composites were prepared by esterification and polycondensation. Findings Non-isothermal kinetic results showed that the high cooling rate hindered the movement of the molecular chain of the composites and made the crystallization peak move toward the low-temperature direction. With the increase of crystallization temperature ( T c ), the melt crystallization rate decreases, but the cold crystallization rate increases. The introduction of OMMT and SiO 2 aerogel condensation affected the nucleation and growth mode of crystals, lengthened the time with a relative crystallinity of 50% ( t 1/2 ) and decreased the crystallization rate. OMMT improved the crystallinity and Avrami index of the composites. Research limitations/implications Effects of thermal insulation functional filler SiO 2 aerogel and co-modified filler OMMT on the crystallization process of PET were studied by non-isothermal crystallization kinetics, and the effects of SiO 2 aerogel and OMMT on the nucleation mechanism of PET were clarified, which provided a theoretical reference for the preparation and performance optimization of PET matrix composites. Originality/value In this study, the OMMT/SiO 2 aerogel/PET composites were prepared by in-situ polymerization, the crystallinity of PET matrix composites was improved, and the effects of OMMT and SiO 2 aerogel on the crystallization process of PET were clarified.