The Research Of Using Silicon Tetrachloride Obtained Silicone Resin

Silicon tetrachloride is the most important by-product in the Polysiliconproduction,that is a corrosive and poisonous liquid, can broken down into silicate andhighly toxic gas hydrogen chloride in the Case of humid air, Has a strong irritant tothe eyes, skin, respiratory tract,and will explode meeting fire; the spillover ofhydrogen chloride gas can make a cough, dizziness, chest tightness and othersymptoms, lead to yields cut and crops, and Costly treatment. With the increase of theyearly total output of polycrystalline silicon, polysilicon production of silicontetrachloride by-product of environmental issues have become increasinglyprominent,therefore, it is highly necessary for the recycling of silicon tetrachloride,turning waste into treasure. In this paper,using silicon tetrachloride prepare into silicapolymer by condensation polymerization, and then modified using epoxy resinprepared excellent film-forming properties for further application. We study thesilicon-oxygen polymers and their synthesis of modified material,and analyze andcharacterizate the target structure and properties.1.Esterification of silicon tetrachloride. We used ethanol and silicon tetrachloride asthe raw material, Controlled the reaction extent by testing chlorine content and PHvalue of the product, respectively, studied the relationship between temperature andchlorine content, reaction time on the chlorine content, silicon tetrachloride/ethanolratio on chlorine content, obtained suitable conditions of esterification, that is Silicontetrachloride/ethanol,=1:4; reaction temperature50℃; reaction time3.5h.。2.The hydrolysis and condensation of TEOS. We controlled the reaction extent bytesting the degree of the viscosity of the product.under acidic conditions，we studiedthe reaction temperature and reaction time influence on the viscosity of products, ratioof TEOS and water influence on the viscosity of the product, Solvent of ethanolcontent influence on the viscosity of hydrolyzate, and the different PH value influenceon the hydrolysis products,Studied different concentrations of NaOH solutioninfluence on the hydrolysis products under alkaline conditions, Obtained the optimalconditions for hydrolysis,that is hydrolysis temperature of50℃, hydrolysis time3h,TEOS: water=1:2, ethanol35%, acid catalyst PH=5.3.Modification of silicon-oxygen polymer.We modified its by epoxy resin,respectively, researched different catalysts, solvents, reaction temperature, reactiontime and epoxy content impact on the performance of the product. investigated hardness, adhesion, film forming, acid resistance, water resistance, storage stabilityand so on. The following conclusions is that,when sulfuric acid as catalyst, themodified temperature50℃, modified time of1hour,35%solvent and epoxy resincontent of30%, the product system is homogeneous,coating fullness and storagestability.4.Characterized the modified and hydrolysis products by IR. The result is that:in thehydrolysis process, occurred the hydrolysis and condensation reactions to becomingsilicon-oxygen polymer; Epoxy resin and silica oligomers is not a simple physicalblend, but the graft polymerization occurred, and the chemical reaction occurs in theepoxy-OH bond, rather than on the epoxy.