Effect of Fumed Silica Content on the Microstructure and Hydrophobicity Recovery of Silicon Rubber
Wang Kang1, 2, Wang Jianguo1, Zheng Feng3, Fang Pengfei3, Peng Xiangyang4, Xu Zhihai4
1. School of Electrical Engineering Wuhan University Wuhan 430072 China; 2. State Grid Jibei Electric Power Company Limited Electric Power Research Institute Beijing 100045 China; 3. Department of Physics & Hubei Nuclear-Solid Physics Key Laboratory Wuhan University Wuhan 430072 China; 4. Guangdong Power Grid Company Electric Power Research Institute Guangzhou 510080 China
Abstract：Hydrophobicity recovery is an important characteristic of silicon rubber. Silica as reinforcing filler is the basic material of silicon rubber composite insulators. In order to study the microstructure and hydrophobicity recovery of silicon rubber with different contents of silica, the silicon rubber samples with different quality contents were refined. The results of the positron lifetime spectra showed fumed silica interacted with rubber chains. Since fumed silica could be served as physical cross-link junction, when the content of fumed silica increased, the cross-link degree of whole system also increased. On the other hand, more fumed silica resulted in bigger size agglomeration. Thus more positrons annihilated in fumed silica, and suppressed the production of Ps. So τ3 increased while I3 and I4 both decreased. Otherwise, after 5 min Ar plasma treatment, the results of the hydrophobicity recovery showed that increasing fumed silica would decrease hydrophobic recovery speed. But too much fumed silica will affect the hydrophobicity recovery of silicone rubber and shorten the lifetime.
[1] 戴罕奇, 梅红伟, 王黎明, 等. 复合绝缘子弱憎水性状态描述方法Ⅰ—— 静态接触角法的适用性[J]. 电工技术学报, 2013, 28(8): 34-46. Dai Hanqi, Mei Hongwei, Wang Liming, et al. Description method Ⅰfor unobvious hydrophobic state of omposite insulators—usability of contact angle method[J]. Transactions of China Electro- technical Society, 2013, 28(8): 34-46. [2] 覃永雄, 虞澜, 傅佳, 等. 长波紫外照射下高温硫化硅橡胶的微观物性及憎水性研究[J]. 电工技术学报, 2014, 29(12): 242-250. Qin Yongxiong, Yu Lan, Fu Jia, et al. Research on microscopic properties and hydrophobicity of high temperature vulcanization silicon rubber long-wave ultraviolet radiation[J]. Transactions of China Electrotechnical Society, 2014, 29(12): 242-250. [3] 张楚岩, 张福增, 陈昌龙, 等. 高海拔地区直流特高压大尺寸复合外绝缘污闪特性研究[J]. 电工技术学报, 2012, 27(12): 20-28. Zhang Chuyan, Zhang Fuzeng, Chen Changlong, et al. Research on pollution flashover characteristics of large-size composite outdoor insulation for UHV DC in high altitude area[J]. Transactions of China Electrotechnical Society, 2012, 27(12): 20-28. [4] 梁英, 陈逸昕, 刘云鹏. 运行复合绝缘子材料的体积电阻率-温度特性研究[J]. 电工技术学报, 2014, 29(10): 312-318. Liang Ying, Chen Yixin, Liu Yunpeng. Research on characteristics of volume-resistivity and temperature for field composite insulators[J]. Transactions of China Electrotechnical Society, 2014, 29(10): 312- 318. [5] 梁英, 靳哲, 刘云鹏, 等. 基于陷阱特性的运行复合绝缘子老化定量评估[J]. 电工技术学报, 2015, 30(18): 189-195. Liang Ying, Jin Zhe, Liu Yunpeng, et al. The quantitative-evaluation on the aging condition of composite insulators based on trap characteristics[J]. Transactions of China Electrotechnical Society, 2015, 30(18): 189-195. [6] 梁英, 李成榕, 丁立健, 等. 合成绝缘子材料的TSC试验研究[J]. 电工技术学报, 2006, 21(2): 13-16. Liang Ying, Li Chengrong, Ding Lijian, et al. An experimental test on TSC of the composite insulators[J]. Transactions of China Electrotechnical Society, 2006, 21(2): 13-16. [7] 胡琴, 袁伟, 舒立春, 等. 电压类型对复合绝缘子覆冰及闪络特性的影响[J]. 电工技术学报, 2015, 30(3): 268-276. Hu Qin, Yuan Wei, Shu Lichun, et al. Influence of voltage types on composite insulator icing and flashover characteristics[J]. Transactions of China Electrotechnical Society, 2015, 30(3): 268-276. [8] Venkatesulu B, Thomas M J. Corona aging studies on silicone rubber nanocomposites[J]. IEEE Transa- ctions on Dielectrics and Electrical Insulation, 2010, 17(2): 625-634. [9] Zhu Y, Haji K, Otsubo M, et al. Surface degradation of silicone rubber exposed to corona discharge[J]. IEEE Transactions on Plasma Science, 2006, 34(4): 1094-1098. [10] Zhu Y, Otsubo M, Honda C, et al. Loss and recovery in hydrophobicity of silicone rubber exposed to corona discharge[J]. Polymer Degradation and Stability, 2006, 91(7): 1448-1454. [11] 梁英, 李成榕, 丁立健, 等. 电晕对HTV硅橡胶憎水性恢复的影响[J]. 高电压技术, 2008, 34(1): 30-32, 40. Liang Ying, Li Chengrong, Ding Lijian, et al. Effect of corona discharge on the hydrophobicity recovery of HTV silicone rubber[J]. High Voltage Engineering, 2008, 34(1): 30-32, 40. [12] Zhu Y, Otsubo M, Honda C. Degradation of polymeric materials exposed to corona discharges[J]. Polymer Testing, 2006, 25(3): 313-317. [13] Hillborg H, Tomczak N, Olàh A, et al. Nanoscale hydrophobic recovery: a chemical force microscopy study of UV/ozone-treated cross-linked poly (dime- thylsiloxane)[J]. Langmuir, 2004, 20(3): 785-794. [14] Béfahy S, Lipnik P, Pardoen T, et al. Thickness and elastic modulus of plasma treated PDMS silica-like surface layer[J]. Langmuir, 2009, 26(5): 3372-3375. [15] Bodas D, Rauch J Y, Khan-Malek C. Surface modification and aging studies of addition-curing silicone rubbers by oxygen plasma[J]. European Polymer Journal, 2008, 44(7): 2130-2139. [16] 王少阶, 陈志权, 王波, 等. 应用正电子谱学[M]. 武汉: 湖北科学技术出版社, 2008. [17] Dai L, StJohn H A W, Bi J, et al. Biomedical coatings by the covalent immobilization of polysaccharides onto gas-plasma-activated polymer surfaces[J]. Surface and Interface Analysis, 2000, 29(1): 46-55. [18] Coulson S R, Woodward I S, Badyal J P S, et al. Ultralow surface energy plasma polymer films[J]. Chemistry of Materials, 2000, 12(7): 2031-2038. [19] Jean Y C, Chen Hongmin, Zhang R, et al. Early stage of deterioration in polymeric coatings detected by positron annihilation spectroscopy[J]. Progress in Organic Coatings, 2005, 52(1): 1-8. [20] Mallon P E, Greyling C J, Vosloo W, et al. Positron annihilation spectroscopy study of high-voltage polydimethylsiloxane (PDMS) insulators[J]. Radi- ation Physics and Chemistry, 2003, 68(3/4): 453-456. [21] 刘艳伟, 芦艾, 邓志华, 等. 乙烯基含量对硅橡胶硫化特性的影响[J]. 功能材料, 2013, 44(4): 488-492. Liu Yanwei, Lu Ai, Deng Zhihua, et al. Effect of vinyl concentration on the characteristics of silicone rubber vulcanization[J]. Functional Materials, 2013, 44(4): 488-492. [22] 束华东, 李小红, 张治军. 表面修饰纳米二氧化硅及其与聚合物的作用[J]. 化学进展, 2008, 20(10): 1509-1514. Shu Huadong, Li Xiaohong, Zhang Zhijun. Surface modified nano-silica and its action on polymer[J]. Progress in Chemistry, 2008, 20(10): 1509-1514. [23] Chien A, Maxwell R, Chambers D, et al. Charac- terization of radiation-induced aging in silica- reinforced polysiloxane composites[J]. Radiation Physics and Chemistry, 2000, 59(5): 493-500. [24] Shu B, Xie H, Li J, et al. Study of fumed silica on the properties of addition-cured room temperature vulcanization silicone rubber[J]. Synthetic Materials Aging and Application, 2008, 37(3): 28-31. [25] Hynek Biederman. Plasma polymer films[M]. London: Imperial College Press, 2004. [26] He Chunqing, Suzuki T, Hamada E, et al. Characterization of polymer films using a slow positron beam[J]. Matrial Research Innovations, 2003, 7(1): 37-41. [27] Liao Kuosung, Chen Hongmin, Awad S, et al. Determination of free-volume properties in polymers without orthopositronium components in positron annihilation lifetime spectroscopy[J]. Macromo- lecules, 2011, 44(17): 6818-6826. [28] Mogensen O E. Spur reaction model of positronium formation[J]. The Journal of Chemical Physics, 2003, 60(3): 998-1004. [29] Eldrup M, Lightbody D, Sherwood J N. The temperature dependence of positron lifetimes in solid pivalic acid[J]. Chemical Physics, 1981, 63(1): 51-58. [30] 王伟良. 热硫化硅橡胶的合成和加工[J]. 有机硅材料, 2011, 25(4): 286-288. Wang Weiliang. Synthesis and processing of heat vulcanized silicone rubber[J]. Silicone Material, 2011, 25(4): 286-288. [31] Berrod G, Vidal A, Papirer E, et al. Reinforcement of siloxane elastomers by silica. Chemical interactions between an oligomer of poly (dimethylsiloxane) and a fumed silica[J]. Journal of Applied Polymer Science, 1981, 26(3): 833-845. [32] Dreiss C A, Cosgrove T, Benton N J, et al. Effect of crosslinking on the mobility of PDMS filled with polysilicate nanoparticles: positron lifetime, rheology and NMR relaxation studies[J]. Polymer, 2007, 48(15): 4419-4428. [33] Meincken M, Berhane T A, Mallon P E. Tracking the hydrophobicity recovery of PDMS compounds using the adhesive force determined by AFM force distance measurements[J]. Polymer, 2005, 46(1): 203-208.
2016, Vol. 31 
