聚碳硅烷热解产物抗氧化性能的研究

在流动氩气中将聚碳硅烷（PCS）于不同温度下进行热解处理制得热解产物,对其进行抗氧化实验,并采用X R D、E D X对PCS热解产物及其氧化产物的物相和成分组成进行表征. 结果表明,PCS于1 000oС的热解产物主要为无定形的SiC、SiO2和C;随着温度的升高,SiC晶体尺寸逐渐增大,1 560oС的热解产物仍由立方SiC、无定形C和SiO2组成;PCS热解产物中的SiO2含量以及SiC的晶化度对其起始氧化温度有一定影响;热解产物中SiO2、SiC氧化形成的SiO2使得PCS热解产物在高温下具有良好的抗氧化性能.

Anti-oxidation property of the pyrolysis products from polycarbosilane

Pyrolysis products of polycarbosilane （PCS） were prepared by a heat treatment method at various temperatures in flowing argon atmosphere, and the anti-oxidation activity of the pyrolysis products was tested at different temperatures under static air atmosphere. The phase and composition of the pyrolysis products and their oxidized products were characterized by X-ray diffraction （XRD） and energy dispersive X-ray spectroscopy （EDX）. The results show that the pyrolysis products of PCS prepared at 1 000 ℃ are mainly composed of amorphous SiC, SiO2 and carbon and the crystal size of cubic SiC increases with the pyrolysis temperature. The pyrolysis products of PCS prepared at 1 560℃ still mainly consist of cubic SiC, amorphous carbon and SiO2, and the content of SiO2 and the crystallinity of SiC of the PCS pyrolysis products have influence on their initial oxidizing temperature. The good anti-oxidation property of PCS pyrolysis products at high temperatures is attributed to the presence of SiO2 in PCS pyrolysis products and partial oxidation of SiC.