Studies On Preparation And Properties Of ABS/MMT Nanocompsites

Polymer/MMT nanocomposite is a new class of material. They can attain excellent mechanical properties, thermal stability and barrier properties at lower clay content. Their potential applications include film, food packing, components in electrical parts, automobile and airplane.In this thesis, ABS/MMT nanocomposites were prepared through several routes including emulsion polymerization process, melt and emulsion mixing. The morphology, mechanical properties and thermal stability of the hybrids were systemically characterized and researched.Na-MMT was modified with hexadecyltrimethylammonium bromide. The structure of organic MMT obtained was then characterized by FTIR and XRD. SAN/MMT was prepared by emulsion polymerization in the presence of MMT. It was found that the MMT was exfoliated and intercalated in SAN resin. The mechanical properties of the SAN/MMT composite were improved.The emulsion graft co-polymerization of styrene and acrylonitrile on to the SBR seed latex in the presence of inorganic MMT was studied. The influence of MMT content on conversion was studied. It was demenstrated that existence of MMT could reduce the conversion of monomer. The grafting degree and grafting efficiency were decreased.The conversion of semi-contionious emulsion polymerization was decreased as the addition of MMT was increased because of the effect of monomer diffusion and decreasing efficiency of intiating agent.ABS/ingoganic MMT hybrids were also prepared by means of mixing the ABS latex with the MMT aqueous dispersion directly. Though the TEM analysis exhibited that some MMT dispersed in nanometer in ABS matrix, the strain strength composites decreased with the MMT content and the thermal stability of composite was not enhanced.The morphology of ABS/MMT composites prepared by means of melting mixingtechnique was characterized by XRD, TEM. The results indicated that the nanometer organic MMT was uniformly dispersed in the ABS matrix. It showed that the mechanical properties, Vicat softening point (VSP) of ABS/organic MMT composites were improved.