A Study on the Morphology and Mechanical Properties of PVC/nano‐SiO₂ Composites

Three methods were used to modify nano‐SiO2 particles with various interfaces and interfacial interactions between the particles and Poly(vinyl chloride) (PVC) matrix. The experimental results show that direct surface treatment of nano‐SiO2 particles with a silane coupling agent (KH‐550) is not effective for improving the mechanical properties of PVC/SiO2 composites. Both ultrasonic oscillations and high energy vibromilling improve the interfacial interactions between SiO2 particles and PVC matrix. With these methods, the aggregation of SiO2 particles was inhibited and a good dispersion of SiO2 particles in PVC matrix was obtained, which improved the mechanical properties of the PVC/SiO2 composite. The mechanical properties of the PVC/SiO2 composite with high energy vibromilling modified SiO2 particles were remarkably improved. Scanning electronic microscopy (SEM), transmission electronic microscopy (TEM), dynamic mechanical analysis (DMA), and theoretical calculations demonstrate these improvements. Keywords: morphologymechanochemicalinterfacePoly(vinyl chloride) (PVC)nano‐SiO2 property Acknowledgments The authors are grateful to the National High Technology Research and Development Program of China (863 Program) (2003AA333010) and the Special Funds for Major State Basic Research Projects of China (2005CB623800) for financial support of this work.