A kind of undercoat for resistor with high temperature and humidity resistance was obtained by modifying epoxy resin with proper nano-SiO2 added at 80℃. The structure, thermal stability, humidity resistance, and morp...A kind of undercoat for resistor with high temperature and humidity resistance was obtained by modifying epoxy resin with proper nano-SiO2 added at 80℃. The structure, thermal stability, humidity resistance, and morphological characteristics of the modified epoxy resin undercoat were studied by electrical tests, infrared spectra （IR） analysis, and scanning electron microscopy （SEM）. The results show that more compact and steady inter-crosslinked network structures are formed in the modified epoxy resin undercoat added with nano-SiO2, which greatly improves the performance of modified epoxy resin undercoat. The undercoat with nano-SiO2 of about 2. 71%, kept for six months at room temperature without flocculating and aggregating, is of good stability, and the surface of painted resistor is uniform, tight and without air holes on it. The varying ratio of resistance with such undercoat painted is less than one in a thousand after high temperature and humidity resistance tests.展开更多
Production of hair and undercoat, type of yak hair fibre, strength, stretched length and ultrastructure of the hair fibre were determined and observed for WY, DY and its offspring in this study. The results showed tha...Production of hair and undercoat, type of yak hair fibre, strength, stretched length and ultrastructure of the hair fibre were determined and observed for WY, DY and its offspring in this study. The results showed that hair yield of the 1/2 WY raised by 19.73% and the undercoat by 14% (P＜0. 01)more than that of the DY. Its strength improved 8. 31% (P＞0.05) more than that of the DY. The stretched length and the ultrastructure of hair fibre were resemblance in the WY and DY.展开更多
文摘A kind of undercoat for resistor with high temperature and humidity resistance was obtained by modifying epoxy resin with proper nano-SiO2 added at 80℃. The structure, thermal stability, humidity resistance, and morphological characteristics of the modified epoxy resin undercoat were studied by electrical tests, infrared spectra （IR） analysis, and scanning electron microscopy （SEM）. The results show that more compact and steady inter-crosslinked network structures are formed in the modified epoxy resin undercoat added with nano-SiO2, which greatly improves the performance of modified epoxy resin undercoat. The undercoat with nano-SiO2 of about 2. 71%, kept for six months at room temperature without flocculating and aggregating, is of good stability, and the surface of painted resistor is uniform, tight and without air holes on it. The varying ratio of resistance with such undercoat painted is less than one in a thousand after high temperature and humidity resistance tests.
文摘Production of hair and undercoat, type of yak hair fibre, strength, stretched length and ultrastructure of the hair fibre were determined and observed for WY, DY and its offspring in this study. The results showed that hair yield of the 1/2 WY raised by 19.73% and the undercoat by 14% (P＜0. 01)more than that of the DY. Its strength improved 8. 31% (P＞0.05) more than that of the DY. The stretched length and the ultrastructure of hair fibre were resemblance in the WY and DY.
