| 摘要: |
| 采用非等温DSC、TG等研究了SiC陶瓷先驱体-液态聚碳硅烷（LPCS）的固化、陶瓷化行为，运用FTIR、XRD、SEM等手段表征了LPCS先驱体在不同温度的裂解产物结构和微观形貌。通过Kissinger、Ozawa及Crane方程得到LPCS先驱体的固化动力学参数：活化能Ea=96. 84kJ/mol，反应级数n=0.94。LPCS先驱体的失重反应主要发生在400～800℃阶段，先驱体中有机官能团逐渐减少，基本完成无机化转变。XRD结果表明，在1000℃以下裂解得到的产物为表面致密的非晶态SiC结构，而在1500℃下裂解产物发生了晶化转变，得到的陶瓷产物主要为β-SiC相。LPCS具有较低的室温粘度（0.25Pa·s）、良好的室温稳定性，适于用作PIP工艺制备SiC基复合材料的先驱体。 |
| 关键词: LPCS先驱体 固化动力学 陶瓷化 SiC陶瓷 |
| 基金项目:国防基础科研项目（JCKY2017203C041） |
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| Curing and Ceramization of A Liquid Polycarbonsilane Precursor |
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Zhu Shibu Zhang Qiang Meng Xiangli Yang Xing Yan Liansheng Zhang Xiaohu Cui Hong
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Xi’an Aerospace Composites Research Institute
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| Abstract: |
| The ceramization and curing behaviors of liquid polycarbosilane (LPCS) precursor for SiC ceramic were investigated by differential scanning calormetry (DSC) and thermogravimetric analysis (TGA). The structures and morphology of ceramic products were characterized by fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD) and scanning electron microscope (SEM). The kinetic parameters of this precursor were calculated by Kissinger, Ozawa and Crane equations, and the results were summarized as following: apparent activation energy (Ea) was 96.84kJ/mol and reaction order was 0.94. The mass loss for LPCS mainly occurred in 400～800℃, in which organic groups decreased and polymer-to-ceramic transformation completed. The XRD results indicated that the ceramic product maintained amorphous structure below 1000℃, and ceramics started to crystallize above 1500℃, resulting in the formation of β-SiC structure. LPCS possessed relative low temperature viscosity (0.25Pa·s) and well stability in air, so LPCS precursor was suitable for preparing SiC composite by means of PIP process. |
| Key words: LPCS precursor curing kinetics ceramization SiC ceramic |
