The effects of natural zeolite and silane coupling agents on melting and crystallization behaviour of polypropylene

Abstract

The thermal characterization of polypropylene (PP) composites containing untreated and treated zeolite with different silane coupling agents was carried out using thermogravimetric analysis (TG) and differential scanning calorimetry (DSC) to investigate the effects of natural zeolite and surface modifiers on melting, crystallization and degradation behaviour of PP. 3-aminopropyltriethoxysilane (AMPTES), methyltriethoxysilane (MTES) and 3-mercaptopropyltrimethoxysilane (MPTMS) were used as surface modifiers at four different concentrations (0.5–2.0 mass%). Thermal analyses indicated that silane treatment and 2–6 mass% zeolite addition have no significant effect on the melting and degradation temperatures of the composites. The crystallization temperatures of the composites were increased due to the nucleating effect of the zeolite. The influence of the modifiers on the interactions between PP and zeolite was determined by the activities of untreated and treated zeolite. The maximum interactions leading to good adhesion were observed in the AMPTES treated composites. Also, non-isothermal crystallization kinetics of the composites was analyzed using Avrami and Kissinger models.