Effect of nano-particles-induced phase inversion on largely improved impact toughness of PVC/α-methylstyrene-acrylonitrile copolymer (α-MSAN)/CPE-matrix composites

By adding nano-silicon dioxide (nano-SiO₂) and chlorinated polyethylene (CPE) into poly (vinyl chloride) (PVC)/α-methylstyrene-acrylonitrile copolymer (α-MSAN) (70/30) blends, much improved toughness was gained. Nano-SiO₂ selectively localize within PVC/α-MSAN, which is due to the different interfacial tension between nano-SiO₂ and polymers. This further changed the melt-viscosity ratio between PVC/α-MSAN and CPE, and thus induces the phase inversion. Such a phase inversion contributes to the nanocomposite's Izod impact strength 14.9-18.6 times higher than PVC/α-MSAN and 1.7-2.3 times higher than PVC/α-MSAN/CPE. Other properties including tensile strength, flexural and thermal properties almost remain constant.