先驱体法制备非晶态SiCNO材料

Preparation of Amorphous SiCNO by Preceramic Precursor

以甲基乙烯基二氯硅烷、乙烯基三氯硅烷、氨基甲酸铵和环己烷作为原料,通过溶剂热合成路线制备出SiCNO陶瓷的液态先驱体。先驱体经1100℃热解后,转变为非晶态SiCNO材料。FT-IR红外分析显示先驱体中含有异氰酸酯官能团。非晶态SiCNO具有良好的高温热稳定性,在1500℃时仍保持无定形状态,1600℃以上时基体中析出Si2N2O和少量的β-SiC相。

Liquid SiCNO precursor was prepared by a solvo-thermal route with ammonium carbanate,methyl vinyl dichlorosilane and vinyl triclorosilicane as raw materials.The amorphous SiCNO was then obtained through the pyrolysis of the liquid precursor around 1100℃.FT-IR analysis indicated that there are isocyanate groups in the precursor.The amorphous SiCNO has favorable thermal stability without any decompositiontill 1500℃.However,at temperature above 1600℃ Si2 N2 O andβ-SiC crystalline phases start to precipitate out of the amorphous matrix.