Research On Synthesis Of Several Important Silicone Products

Organic silicon compounds play important role in the clothing,food,accommodation,transportation,beauty,the sky and sea and many areas.They have become an indispensable part of people's daily lives.Their development are in full swing now.This paper would deeply study and discuss synthesis of fluoride silane coupling agent,vinyl silane coupling agent,vinyl fluorosilicone oil.In this paper,we prepared homogeneous and heterogeneous platinum catalysts used in the synthesis of 3,3,3-trifluoropropyltrichlorosilane.The experimental results showed that prepared homogeneous chloroplatinic acid-polymethylvinylsiloxane catalyst and heterogeneous diatomite load polymethylvinylsiloxane platinum complexe both had high catalytic activity and stability in the hydrosilylation reaction.When under the homogeneous catalyst,the activation temperature of 50°C,the reaction temperature of 140°C,catalyst in the amount of 1.2x10^-4 mol, the yield could reach 85.7%. Under the heterogeneous catalyst,the yield was 80%,and the catalyst after fourth repeated use found no deactivation.The catalytic mechanism of homogeneous catalysis also was conducted a preliminary study.3,3,3-Trifluoropropyltrimethoxysilane was synthesized by means of solution method with 3,3,3-trifluoropropyltrichlorosilane and methanol as raw materials.The key was to remove HCI and reduced the incidence of side reaction.The influence of reaction conditions,such as nitrogen flow rate,reaction temperature,ratio of material,solvents and the way of dropping,on the yield of product was discussed.The optimum conditions for synthesizing 3,3,3-trifluoropropyltrimethoxysilane were established.And the yield of product could reach 89.4%.After counteracting and pressure distillation,144-145°C fracton collected,the purity of 3,3,3-trifluoropropyltrimethoxydilane could reach 99%.Three kinds of catalysts,which were chloroplatinic acid-isopropyl alcohol,chloroplatinic acid-polymethylvinylsiloxane and chloroplatinic acid-triphenyl phosphine were prepared.The acticity and selectivity of these catalysts for the hydrosilation of acetylene with triethoxysilane were measured.The influence of ligand on thermal stability of catalysts was investigated.And the influence of reaction conditions,such as reaction temperature,flow rate of acetylene,sol?ent types,molar ratio of chloroplatinic acid-polymethylvinylsiloxane and triethoxysilane,PPh3/H2PtCl6 molar ratio et al,on the yield of product was discussed.The resultsindicated that chloroplatinic acid-isopropyl's activity was good,but its selectivity was low, only 64%.The chloroplatinic acid-polymethylvinylsiloxane and chloroplatinic acid -triphenyl phosphine showed excellent catalytic activity and selecticity in the hydrosilation.Under certain conditions,the yield of product were both more than 90%.The selectivity of once addition product were 100% and 98.5%respectively.Under alkaline catalyst,vinyl fluorosilicon oil which can be applied as a lubricant base oil was synthesized with D3F and D4 as raw materials and ViVi as blocking agent.The preparation process of vinyl fluorosilicon oil was studied.The influence of reaction conditions,such as water in the reaction system,the type and amount of catalysts,amount of ViVi,reaction time, reaction temperature,the removal of low viscosity,et al,on the polymerization reaction was investigated.The preparation process was simple and the raw materials were easy to get.It was easier to control the molecular weight of product and it made the distribution of fluorosilicones molecular structure tend to be more reasonable.By controlling the amount of ViVi,we could obtain different viscosity of vinyl fluorosilicon oils.For example,when the dosage of raw materials D4 and D3F were 50 g and 125 g,ViVi blocking agent was equal to 0.23% of the total weight of materials,catalyst was equal to 0.02% of the total weight of materials,the reaction temperature was ll0°C,the reaction time was 6 hours,vinyl Fluorosilicone oil which viscosity was 15.1Pa·S could be obtained.The yield of product was 90%.And the anionic reaction mechanism of D3F, D4 and ViVi was in a prelimimary discussion.