Preparation And Application Of Novel Siloxane Alicyclic Epoxy Resins

Epoxy resin has excellent adhesive properties,good adhesion and almost no shrinkage during curing.Silicone resin has excellent flexibility,low surface energy and good thermal stability.Epoxy resins and vinyl groups in epoxy resin can be reacted with the amines and hydrogen bonds of organosilicon to produce modified epoxy resin,which can improve the properties of epoxy resin by introducing flexible and hot stable silicon oxygen chains in the structure.Two novel siloxane alicyclic epoxy resins were synthesized with 1,1,3,3-Tetramethyldisiloxane(TDS),1,1,3,3,5,5,7,7-Octamethyltetrasiloxane(OTS)and 1,2-Epoxy-4-vinylcyclohexane(EVC)as raw materials.The optimum reaction conditions for the Tetramethyldisiloxane cycloaliphatic epoxy resin are as follows: EVC and catalyst are mixed,heating to 70 degrees centigrade and TDS,the molar ratio of EVC to TDS is 2:1,the catalyst is 0.5% of TDS mass,and the product is obtained at 70 centigrade for 4 hours after dropping.The optimum reaction conditions for the Octamethyl tetrasiloxane cycloaliphatic epoxy resin are as follows: EVC and catalyst are mixed,heating to 130 degrees centigrade and OTS,the molar ratio of EVC to OTS is 2.2:1,the catalyst is 0.6% of OTS mass,and the product is obtained at 130 centigrade for 6 hours after dropping.The characteristics of two novel siloxane alicyclic epoxy resins are basically consistent through the analysis of IR and 1H NMR spectra.The novel siloxane alicyclic epoxy resins as UV curable photosensitive prepolymer has low hardness,but adhesion,flexibility and impact strength are superior.The novel siloxane alicyclic epoxy resins has better dilution effect on the bisphenol A epoxy resin E-51.It can be used as an excellent epoxy resin active diluent.Four methyl two siloxane alicyclic epoxy resin can obviously improve the tensile strength,and eight methyl four siloxane alicyclic ring oxygen resin can improve adhesion,flexibility and impact strength.The synthetic Octamethyl tetrasiloxane cycloaliphatic epoxy resin was added to the bisphenol A epoxy resin E-51 as a toughening agent to improve the flexibility of the epoxy system cured by the anhydride.The film was prepared to test the tensile strength,pencil hardness,adhesion,flexibility,impact strength and other data.The test results showed that the best comprehensive performance was found when the amount of addition was 10%.