Effects of intercalant on the dispersibility of silicate layers in clay-dispersed nanocomposite of poly(styrene-co-acrylonitrile) copolymer

Abstract

Clay/poly(styrene-co-acrylonitrile) copolymer (SAN) hybrids have been prepared by simple meltmixing of two components, SAN and organophilic clays with a twin screw extruder. Effects of intercalant on the dispersibility, of silicate layers in clay-dispersed nanocomposite were studied by using five different organophilic clays modified with the intercalants of different chemical structures and different fractions of intercalant. The dispersibility of 10-Angstrom-thick silicate layers of clay in the hybrid was investigated by using an X-ray diffractometer and a transmission electron microscope. It was found that if the fraction of intercalant in the organophilic clay becomes too high, SAN is difficult to intercalate into the inter-gallery of silicate layers in the hybrid prepared at 180degreesC, and thus the hybrid shows poor dispersibility of silicate layers. The flexural modulus of the hybrid increases as the dispersibility of silicate layers in the hybrid increases.