Study On Preparation Process Of Organic Silicon Release Agent

Rubber and plastics industry has maintained a high growth rate in our country, since21st century. The production of rubber and plastics ranks first in the world. With the rapid development of this industry, release agent is used more and more widely, and become a hot topic. In this paper, the preparation process of organic silicon release agent was explored. It will provide references for future research.Firstly, the preparation conditions of polysiloxane emulsion was explored by dimethylcyclosiloxane(DMC) ring opening and polymerization by means of cationic emulsion polymerization. In this experiment, cetrimoniumbromide(CTAB) was used as emulsifier, cetrimonumbromide(OP-lO) as auxiliary emulsifier and potassium hydroxide(KOH) as catalyst. Orthogonal test table design was used to optimize the preparation conditions. Through range and variance analysis, the optimum conditions were:dropping time of pre-emulsion:lOOmin, catalyst:1.60%(w%), emulsifier:6%-8%, mixture ratio(CTAB:OP-10):1:2.Secondly, methyl ltriethoxysilane which made from methyl tri-chlorosilane and ethanol used as cross linker to cross-linking polysiloxane for the comprehensive utilization of industrial by-product methyl tri-chlorosilane and to reduce the production cost of silicone release agent,. The effects of feeding method, ethanol drops speed and nitrogen bubble volume on the alcoholysis reaction were explored. Finally, the method of adding methyl tri-chlorosilane to reaction system, the dropping speed of ethanol to methyl tri-chlorosilane controlled by the amount of HCl and nitrogen bubble volume0.2mJ/h were selected.Finally, methyl ltriethoxysilane was used as cross linker to cross-linking polysiloxane, and trimethyl chlorosilane used as endcapper to end the reaction. The optimum conditions of the cross linking and blocking reaction were explored. When cross-linking temperature was60±5℃, cross-linking time was4h, the amount of cross linker was34%-46%, the amount of endcapper was5%-7%, cross linking and blocking reaction. Especially, the pH value of system should be regulated to6-7before the blocking reaction.The synthesis process of organic silicon release agent developed in this thesis was simple, easy to operate, low cost, and avoid floating oil, yellowing and poor stability. The comprehensive utilization methods of industrial by-products showed great economic-benefits and environmental benefits, and promising potential for industrial application. In addition, this work provided a clear target for future research.