In the thesis, The modified PVC composite materials were prepared by three methods, Including the adding of nanometric organic montmorillonite, blending with SAN resin and adding modifier.1. Partially exfoliated PMMA/MMT nanocomposites were prepared via the intercalative emulsion polymerization and characterized by means of WAXD, SEM, TGA, DMA, DSC and rheometer. The modified PVC composite materials were prepared by adding the nanometric modifiers, which were synthesized via the intercalative emulsion polymerization. The structure、 processing fluid ,mechanical properties and thermal properties ,rheological properties were studied. It was showed that in comparison with pure PVC resins, these modified PVC/OMMT composite materials performed improved process ability and mechanical and thermal properties.2. The modified PVC composite materials were prepared by adding modifier. We studied the modified PVC composite materials by means of WAXD, SEM, TGA and DSC, DMA, rheometer, FT-IR. The structure, processing fluid properties, mechanical properties, thermal properties, and rheological properties were studied. It was showed that in comparison with pure PVC resins, these modified composite materials performed improved process ability and mechanical properties. And we found the modifier has strong interaction with PVC resin.3. Because of good compatibility with PVC and the high tensile strength of SAN,We modified PVC with SAN by means of melting blending.