Solution Polymerization In Situ Intercalative Preparation Of Polymer Matrix / Montmorillonite Nano-composite Materials

In recent years, organic-inorganic nanocomposites have attracted great interests from scientists. This new type of composites exhibits properties far superior to those of separate components, which makes them widely used in many field. An effective approach of preparing organic/inorganic composites is intercalation, through which polymers are intercalated between sheets of inorganic materials such as montmorillonite(MMT). Polymer/layered silicate nanocomposite is a new excitement of material field, where a single or more extended polymer chain is intercalated between the silicate layers resulting in a well ordered multiplayer morphology built up with alternating polymeric and inorganic layers, or the silicate layers delaminated and dispersed uniformly in a continuous polymer matrix. The synergic effect of silicate layers and polymer molecule chains gives full play to stiffness, thermal stability and size stability of inorganic silicate and the toughness and good processing properties of polymer, giving rise to a high performance polymer nanocomposites even with a tiny amount of layered silicate content. The experiments show that montmorillonite is dispersed homogeneously in polyimide in nanoscale. Thanks to this special structure, polymer/nanocomposites have had better properties than the neat polymer.In situ-polymerizations originates from the so-called polymerization-filling technique of last century. This method consists in anchoring in a first step , a catalyst or MAO activated metallocene on to a filler surface, and then in situ-polymerizing monomer directly from the surface treated fillers. As the polymerization proceeded, the layered silicate could be exfoliated by polymerization heat and polymer/layered silicate nanocomposites can be in situ-produced. Situ-polymerization overrides entropic and enthalpic barriers associated with intercalating the a polar or an unpolar polymer with polar silicate, which make it easier to produce nanocomposites.In this paper, intercative process theories which include thermodynamical analysis, kinetical analysis and phase behavior simulation are first discussed. Then the influence factors are analysed and the feasibility of this paper research task is also analysed.Poly(vinyl acetate)(PVAc),Poly(maleic anhydride)(PMA) and Poly(epoxysuccinic acid)(PESA)/montmorillonite nanocomposites are synthesized by using vinyl acetate,maleic anhydride and epoxysuccinic acid as monomers, as well as organic montmorillonite as reinforcement. The suitable process conditions are reached and the structure and properties are characterized by FTIR, XRD and DSC and so on.