| Polymer nanometer-hybrid materials are of important parts in the field of nanoscience and nanotechnology. The process to make the hybrids is the one of most important methods in the preparation of the high performance polymer material. Polyacrylate has good processability, plasticity and functionality makes it is one of the best carriers of hybrid materials.In this paper the preparation and properties of nano silica /polyacrylate were stuied. If the nano particles were dispersed into the emulsion directly, the stable dispersion in nano size was a difficult problem because nano SiO2 are strong hydrophilic and are of tendency to reunite. The nano sized polyacrylate latex particles were first prepared, the core/shell composite latex were prepared with MPS-modified silica particles as seeds and polyacrylate as shell on the basic of the study on pure polyacrylate latex. The agglomeration problem of nano particles had been solved, and the force properties had been greatly improved.The pure acrylic emulsion was synthesized by seeded emulsion polymerization. The effects on the latex properties and particles size were investigated as the types and amount of emulsifier, reaction temperature, shell monomer adding velocity and the ratio of seeded monomer. The good properties of pure polyacrylate which had particles diameter less than 100nm could be got when choosen anionic emulsifier SDS and nonionic emulsifier OP-10 as composite emulsifier, quality ratio of the two emulsifier was (SDS): (OP-10)=2:1, the reaction temperature was 75℃, the shell monomer adding velocity was 0.34ml/min, the seeded monomer ratio was 15%.On the basic of the study on pure polyacrylate, the core/shell composite latex particalcs with silica as core and crosslinked polyacrylate as shell were prepared via seed emulsion polymerization method. The effects of the amount of silica, the time of silica modification and the amount of coupling agent on the latex properties were researched. In terms of force properties, the tensile strength and the elongation rate at break of composite latex film were improved 47.27% and 17.48% respectively compared to the pureacylate film, owing to the chemical bond between the coupling agent on silica surface and acrylate monomer which can substain to greater tensile force.The diameters of the composite latex particles were investigated by the Laser Paticle Size Analyzer, the result showed that the latex particle with 70.nm could be obtained when the amount of silica was 0.18%, the silica modification time was 3h and the coupling agent was 3.75%. The diameter of particles increased with the increasing of the amount of silica. FTIR confirmed the MPS was successfully grafted to the silica surface and the monomer and MPS were completely reactioned because the the absorption peak of C=C bond between 1620 cm-1-1680 cm-1dissapeared entirely.TEM micrographs showed the core/shell structure of the composite latex, and no agglomeration between the particles. ESEM micrographs on the composite film demonstrated the modified silica has good compatability with polymer. And the film etched by aceton was first investigate by ESEM showed the composite was a highly cross-linked network.Different methods were used to prepare silica gel/polyacrylate composite, star-like material with about 1.5cm diameter were originally abtained. And the formation mechanism were studied by ESEM through etching the film. The silica gel/polyacrylate emulsion was successfully prepared by in situ polymerizaion.The heat-insulation coating were originally prepared by using nano composite emulsion of silica/polyacrylate and silica gel/polyacrylate as matrix, comparation to the coating prepared by using polyacrylate with directlly mixed silica and pure polyacrylate as matrix. The results indicated that the nano coating had better properties on heat-insulation, water-resistance, acid-resistance, base-resistance than directlly blend coating had.
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