Hexaphenyl cyclotrisilazane was synthesized from diphenyl dichlorosilane and ammonia with toluene as solvent.The effects of input material concentration, reaction temperature, ammonia flow rate and separation method on product yield were investigated.The structure of hexaphenyl cyclotrisilazane was characterized with FTIR and XRD.It was found that when diphenyl dichlorosilane concentration was 0.96 mol·L -1 , reaction temperature was 111—112℃,NH3 flow rate was 0.02 m3·h -1 , the yield of hexaphenyl cyclotrisilazane could reach 91.1%.Using ammonia water was better than hot filtration to weed out ammonium chloride at the period of product separation.It enhanced separation efficiency and simplified the process.At the same time it also decreased pollution to the environment by reducing volatile matter of toluene.
