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The polystyrene foam plastics are used widely day by day. They bring great convenienceto people, but, the polystyrene foaln do not degrades under the natural condition, so they havebecome everyone’s talking issues. So the people at home and abroad have reseached theseproblems thoroughly and extensively.Today the EPS recycling use still mainly manifested in:1. make the light qualitybuilding materials.2. paralyzed for getting the monomer styrene or the oil product.3. makethe coating and the adhesive and so on.The experiment is divided into three parts. The first part is PS grafting trials. Second,nano-SiO2is modified by silane coupling agent KH-570. The third part is making nanocomposite coating by dispersion of nano-SiO2to emulsion.In the first experiment we explored that the maleic anhydride （MAH） grafted polystyreneprocess conditions and determined the optimal grafting reaction conditions:1%BPO,3%MAH, the reaction time3h, temperature100℃, the adding way of MAH3:2:1. In theemulsion experiments, the optimal emulsion reaction conditions: BPO1%, MAH3%, thereaction time3h, temperature100℃.In the experiment nonionic emulsifier OP-10and anionic emulsifier sodium dodecylbenzene sulfonate are selected to form the composite as stabilizers. when the emulsifieramount is up to2%, the composite latex is stable.In the experiment nano-SiO2was modified by silane coupling agent KH-570. With thepoor orthogonal test we analysed influence factors of various reaction conditions. The resultsshowed that the optimal reaction conditions are3.5%KH-570,5%nano-SiO2, reaction time6h, temperature70℃.In the experiment nano-SiO2/polyacrylate composite latex was prepared by blendingmethod. It was found that the hardness, adhesion and weatherability of the composite latexwere obviously improved by addition of nano-SiO2. The results showed that the optimalreaction conditions are modified2.5%nano-SiO2, the reaction time6h, temperature70℃,1%KH-570and KH-560,15%phthalate.
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