Preparation And Properties Of Ceramicizable Adhesives For High-temperature Packaging

Ceramic matrix composites are high-temperature structural materials with excellent performance,in order to make ceramic materials can be used to bond components with complex structure,we proposed the idea of high temperature resistant ceramic adhesive.This article mainly prepared a methyl phenyl silicone resin,the?-aminopropyltriethoxysilane coupling agent?KH550?is used as a treatment agent,and TiB₂ ceramic powder is added as a filler to methylphenyl silicone resin to prepare a ceramic adhesive,which is used for bonding of packaging materials under high temperature environment.First,methylphenyl silicone resin was prepared by hydrolytic polycondensation,we explored the effects of different catalysts and solvents on the thermal stability of silicone resin.Through infrared spectroscopy analysis,the absorption peak of benzene ring appeared between 1700 cm^-1-2000 cm^-1,the absorption peak of Si-CH₃ at 1250 cm^-1,and an absorption peak of Si-O-Si bond at 1000 cm^-1-1100 cm^-1,it proves that methyl phenyl silicone resin is synthesized under different catalyst and solvent conditions.Among them,in the silicone resin synthesized with four catalysts of hydrochloric acid,sodium hydroxide,potassium hydroxide and tetramethylammonium hydroxide,silicone resin synthesized with potassium hydroxide as the catalyst has the best heat resistance,the weight loss rate in nitrogen atmosphere is only23%;In the silicone resin synthesized with four solvents of 1,4-dioxane,acetone,dichloromethane and tetrahydrofuran,the silicone resin synthesized with methylene chloride as the solvent has the smallest thermal weight loss rate,and the thermal weight loss rate in a nitrogen atmosphere is 17%.Secondly,TiB2 ceramic powder used as filler was surface modified with three silane coupling agents.Characterize the ceramic powder before and after modification by infrared spectroscopy,after comparison:it was found that the infrared spectrum of the treated TiB2ceramic powder,the characteristic peaks of C-H belonging to-CH₃ and-CH₂-on the silane coupling agent appeared at 2960 cm^-1and 2842 cm^-1,it proves that the modification is successful,the average particle size of KH550 modified ceramic powder particles is 1.2?m.The modification effect of TiB2 ceramic powder is the best under the process conditions of ball milling speed of 500 r/min,ceramic powder/KH550 hydrolysate ratio of 50:4,and ball milling time of 2 h.Finally,we used the silicone resin and modified TiB₂ ceramic powder to prepare a new adhesive.The study found that when the amount of TiB2 ceramic powder filler is 20 wt%,the heat loss of the ceramic adhesive can be reduced by 30%.When the addition amount of TiB2ceramic powder filler is 40 wt%,the adhesive strength can reach 6.86 MPa after curing,when the temperature reaches 1000^oC,the bonding strength of the adhesive can reach 20.86 MPa.The modified TiB₂ ceramic powder has better compatibility and dispersion with silicone resin.