| Silane-graft-epoxy water dispersion was synthesized by copolymerization of epoxy resin, vinyltriethoxysilane (VTES), methylacrylic acid (MAA), and styrene (St). All kinds of factors which affect the polymerization and the properties of the epoxy water dispersion were analyzed in detail. The dynamics of the copolymerization was studied. Furthermore, the cure of the silane-graft-epoxy dispersion with different cure agent was studied. The physical properties of the cured film were measured in order to gain top-quality film. Meanwhile, initial research on the modified epoxy used in anlistatig field was explored.The structure of grafted copolymer was characterized by Fourier Transform Infrared Spectroscopy (FTIR). Results show that chemical reacting between epoxy and vinyltriethoxysilane (VTES) has occurred indeed. And function group -COOH who endues epoxy hydrophilic property is found in the FTIR curves. After optimizing all kinds of factors such as material formulation, temperature, content of BPO and neutralization degree and so on., study shows that under 115 ℃, when BPO content is about 8-12% of monomer, VTES content is 3-6%, and neutralization degree is 70-90%, stable silane grafted epoxy dispersion can be synthesized, and the conversion percentage of monomer is about 99%, graft percentage is about 41 %, particle size is about 100nm.The DSC results show that the glass transition temperature Tg of silane-graft-epoxy polymer changes from 84.0 ℃ to 73.6℃ because of silicone chain was brought in epoxy molecule. And it is found that the cure reaction occur in two temperature range, about 90 ℃ and about 120 ℃, under which the epoxy reacts with cure agent and reacts itself correspondingly. The TGA results show that the degradation of cured film can be divided into two step, both of the maximum weight loss velocity temperature tmax1 and tmax2 of the two step are increased to 287.3 ℃, 481.6 ℃ from 224 ℃ , 469.2 ℃, and rate of residual carbon ω improves from 10.6% to17.6%. The heat stability, water resistance, adhesion, flexibility of the cured film made from silane-graft-epoxy dispersion are all improved compared with the filmmade from ungrafted epoxy dispersion. It is mentionable that the quality of the film is excellent which cured without other cure agent.Water-soluble, conducting polyanline (PANI) synthesized by Enzyme catalyzing was add into the silane modified epoxy dispersion, and then cured with cure agent. The electrical resistivity of the film is2.73 × 10~6 Ω·cm, thus the film has antistatic property. And the adhesion, pencil hardness of the film are similarly to the filmwithout PANI. However, water resistance of the film is worse.
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