微波辐射时间对木质陶瓷导电性能影响的研究

Effect of microwave irradiation time on electroconductive property of woodceramics derived from carbonizing tobacco stems/phenolic resin composites

以烟杆和酚醛树脂为原料,采用微波辐射制备了高导电性能的烟杆基木质陶瓷。同时,研究了微波辐射时间对木质陶瓷体积电阻率的影响,并采用X射线衍射技术、激光喇曼光谱和扫描电镜对其微观结构进行了研究。实验结果表明:与常规加热制备木质陶瓷相比,采用微波辐射的方法可将制备时间缩短99.4%。当微波辐射时间为80s时,木质陶瓷的体积电阻率仅为0.97Ω·cm。通过样品XRD谱图和激光喇曼谱图的分析,随着微波辐射时间的延长,样品有序化程度的提高,根据Tuinstra-Koening经验公式计算所得的石墨微晶面网直径La与通过XRD图谱计算得到的值相近。通过SEM观察可知,当微波辐射时间达到80s时,样品中由酚醛树脂形成的玻璃炭与由烟杆炭形成的无定形炭已融合为一个整体,呈多孔状。

A kind of high electroconductive woodceramics derived from carbonizing tobacco stems impregnated with phenolic resin by microwave irradiation was prepared, and effect of microwave irradiation time on volume electrical resistivity of the woodceramies was investigated. The laser Raman spectroscopy and X-ray diffraction （XRD） techniques were applied to investigate the microstrueture of woodceramies. The experimental results show that the preparation time by microwave irradiation is 0.6% of conventional processing, and the volume electrical resistivity of the woodceramics prepared by microwave irradiation for 80s is 0.97Ω.cm. Through the analysis of XRD patterns and Raman spectra, it is found that the degree of disorder of the woodceramics decreases with the prolonging of microwave irradiation time. And the trend of Lα which is calculated by using Tuinstra-Koening empirical relation is close to the result of Scherrer equation of XRD technique. According to SEM observation, the samples obtained by microwave irradiation for 80s, tobacco stems-originated amorphous carbon and glass-like carbon generated from phenolic resin combines into a whole and the sample appears porous.