Critical Role of Interfacial Structures in Degradation and Stabilization of Polypropylene/SiO₂ Composites

Abstract

To clarify the origin of rapid degradation of polypropylene (PP)-based composites with inorganic fillers, infrared microscope study was performed for PP/SiO₂ composites. Thermal and photo degradations of PP were greatly enhanced around SiO₂ particles, as a result of facile volatilization of stabilizer from loosely connected interfaces between the PP matrix and SiO₂ particles. Organic modification of SiO₂ surfaces improved the connection at the interfaces and notably suppressed the volatilization of stabilizer. Thus, the critical role of interfacial structures was reported for the first time in the degradation and stabilization of PP-based composites.