Synthesis And Properties Of Silicone Fabric Waterproofing Agent

Silicone is a kind of compound with silicon-oxygen bond as the main chain structure,with low surface tension,high compressibility chemical stability and other excellent properties,which is widely used in aviation,medical,textile,construction and other fields.The main chain structure of silicone is soft,and the side chain can be connected to other functional groups through silicon atoms,giving it unique properties.As a common hydrophobic group,the long-chain alkyl group is grafted into the silicone oil chain and used as a fabric finishing agent,which not only can enhance the waterproof performance of the fabric,but also has the characteristics of lubricity and softness,and can be used in the fabric with multi-functional characteristics.In this paper,three kinds of modified silicone oils with different end groups were prepared by bulk polymerization,and their emulsion stability and fabric application performance were evaluated.The main research contents and results were shown as follows:（1）Using octamethylcyclotetrasiloxane and dodecyldimethoxysilane as raw materials,hexamethyldisiloxane as the blocking agent,and tetramethyl ammonium hydroxide as the catalyst,long chain alkyl methyl modified silicone oil was prepared.When the mass ratio of D4 to coupling agent is 100 g:3 g at 100oC with 3 h,and the amount of catalyst TMAH accounts for 0.08%of the total mass,the maximum viscosity of methyl silicone oil was 1536 m.The greater the viscosity of silicone oil,the better the softness of the fabric,and its structure was characterized by FTIR.The milky white opaque emulsion had an average particle size of 460 nm.After finishing the application on the fabric,it could make the fabric have a certain waterproof and softness.（2）Using linear silicone oil PMX-0156,dodecyldimethoxysilane as raw materials,and tetramethylammonium hydroxide as a catalyst,long-chain alkyl hydroxyl modified silicone oil was prepared.Choosing composite nonionic AEO-3and AEO-9 as emulsifiers,a milky white opaque emulsion with an average particle size of 444 nm was obtained,and its structure was characterized by FTIR.The application effect of the emulsion on fabric finishing was discussed.The results showed that when the mass concentration of the finishing liquid is 50 g·L^-1with p H 6,and the baking time was 90 s,the finished fabric had better waterproof effect.（3）Amino-terminated intermediate Ez-201 was prepared from 1,3-di（3-glycidylpropyl）-1,1,3,3-tetramethyldisiloxane and polyetheramine.The results showed that when n（ZC-100）:n（D230）=1:2 at 90oC with 5 h,the stability of Ez-201was the best.Using octamethylcyclotetrasiloxane,Ez-201,co-hydrolysate of dodecyl dimethoxysilane and dodecyl trimethoxysilane as raw materials,and tetramethyl ammonium hydroxide as catalyst,a long chain alkyl amino modified silicone oil was prepared,and its structure was characterized by FTIR and ¹H-NMR.After emulsification,a translucent emulsion with blue light was obtained,and the average particle size of the emulsion was 55 nm.The effect of emulsifier dosage,fabric baking time,p H value on the application effect of amino silicone oil emulsion were discussed.The results showed that when the amount of emulsifier was 20%,the p H of the finishing solution was 6 and the baking time was 90 s,the water contact angle of the fabric surface reached 151.1°,and the comprehensive performance was the best.