摘要
用异丙醇铝改性支化结构聚硅氮烷合成了两种铝含量的聚铝硅氮烷(PASZ),采用FTIR、~1H-NMR对其结构进行了表征。结果表明,PASZ前驱体结构中含有Si-N、A1-N等化学键,DSC表明前驱体在引发剂DCP的存在下可在较低温度下进行固化,TGA表明在N2中1000℃下PASZ11和PASZ41热解残留率分别为65.9%和69.5%。用XRD和SEM研究了SiAlCN陶瓷产物的结构与性能。结果表明,温度和铝含量越高,SiAlCN转化陶瓷越容易形成多铝红柱石晶体,在1200℃空气中氧化了5h后,SiAlCN41陶瓷表面形成了较为致密的氧化层,厚度约为5μm左右。
In this paper,the polyaluminasilazanes(PASZ) with different Al contents were prepared via the reaction between aluminum isopropoxide and branched polysilazane.Their structure was characterized by FFIR,~1HNMR.And the result showed that the backbone of the PASZ precursor contained Si-N,Al-N and so on.DSC indicated the precursor could be cured at lower temperature in the presence of initiator DCP.TGA showed that the ceramic yields of cured PASZ11 and PASZ41 were 65.9%and 69.5%respectively.The structure and properties of SiAlCN ceramic products were studied by SEM and XRD.X-ray patterns showed that with increasing aluminum content and temperature,crystallization ability of amorphous SiAlCN ceramics increased.SEM indicated that after oxidation 5hours in air,a dense oxide layer appeared on the of SiAlCN41 ceramic with about 5μm thickness.
引文
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