HDPE/HIPS/CB复合材料的制备及PTC性能

以高抗冲击聚苯乙烯(HIPS)和高密度聚乙烯(HDPE)为基体,炭黑(CB)为导电填料,采用熔融法制备聚合物基正电阻率温度系数效应(PTC)复合材料.通过扫描电子显微镜(SEM)研究了CB在复合材料两相基体中的选择分布,采用热敏电阻温度(RT)曲线测试仪研究复合材料PTC性能随CB含量的变化规律.结果表明,在HIPS/CB体系中加入HDPE后,复合材料的渗流阈值降低,PTC强度增强,耐电压强度有所提高.     

Columnar growth of crystalline silicon films on aluminium-coated glass by inductively coupled plasma CVD at room temperature

Silicon films were grown on aluminium-coated glass by inductively coupled plasma CVD at room temperature using a mixture of SiH₄ and H₂ as the source gas. The microstructure of the films was evaluated using Raman spectroscopy, scanning electron microscopy and atomic force microscopy. It was found that the films are composed of columnar grains and their surfaces show a random and uniform distribution of silicon nanocones. Such a microstructure is highly advantageous to the application of the films in solar cells and electron emission devices. Field electron emission measurement of the films demonstrated that the threshold field strength is as low as ～9.8V/μm and the electron emission characteristic is reproducible. In addition, a mechanism is suggested for the columnar growth of crystalline silicon films on aluminium-coated glass at room temperature.