SiO2中空微球/HTV复合材料制备与性能研究
文献类型:学位论文
作者 | 钱西慧 |
学位类别 | 硕士 |
答辩日期 | 2016-07 |
授予单位 | 中国科学院研究生院 |
授予地点 | 北京 |
导师 | 张冬海 ; 陈运法 |
关键词 | SiO2中空微球 高温硫化硅橡胶 电绝缘 力学性能 复合材料 |
学位专业 | 材料工程 |
中文摘要 | 超高压和特高压输电网络是智能电网的骨架和核心,其成功实施的关键因素之一是输变电线路的绝缘防护。以高温硫化硅橡胶(HTV)为防污闪基材的复合绝缘子因成本低、强度高、质量轻、耐污闪、不易破碎、维护方便等优点,在高压外绝缘防护应用日益广泛。但其体积电阻率、击穿强度等关键绝缘性能与电工陶瓷、玻璃相差较远,限制了其在超、特高压绝缘防护中的应用。本文针对上述问题,制备了亚微米SiO2中空微球,考察其对HTV力学性能、体积电阻率、击穿性能、介电性能等的影响。主要研究内容与结果如下:1. SiO2中空微球制备通过模板法制备了尺寸、粒径可控的SiO2中空微球。中空微球的平均粒径分别为279 nm、408 nm、491 nm、550 nm、574 nm;平均壁厚分别为10.9 nm、10.3 nm、11.9 nm、16.4 nm,12.4 nm;比表面积分别为163 m2/g、163 m2/g、151 m2/g、141 m2/g、193 m2/g。2. SiO2中空微球对HTV力学性能的影响(1)研究了SiO2中空微球(550 nm)含量对HTV力学性能的影响:复合材料拉伸强度、断裂伸长率随中空微球含量增大而逐渐增大,含量为5 phr时,拉伸强度提高至1.35 MPa,断裂伸长率为237%。优于同等含量气相SiO2的补强效果。(2)研究了SiO2中空微球粒径对HTV力学性能的影响:含量为5 phr,粒径大小分别为279 nm、408 nm、491 nm、574 nm的HTV复合材料拉伸强度分别为0.97 MPa、1.30 MPa、1.26 MPa、1.22 MPa,断裂伸长率分别为189%、208%、207%、205%。408 nm SiO2中空微球/HTV力学性能较优。(3)研究了408 nm SiO2中空微球和PS-SiO2实心微球对复合材料力学性能的影响:SiO2中空微球/HTV和PS-SiO2/HTV复合材料拉伸强度和断裂伸长率分别为1.30 MPa、208%和1.17 MPa、207%。实心微球的拉伸强度稍差于中空微球。3. SiO2中空微球对HTV电性能的影响(1)研究了SiO2中空微球(550 nm)含量对HTV电性能的影响:加入SiO2中空微球后,复合材料体积电阻率由5.3×1015 Ω·cm提升至1017 Ω·cm数量级,随含量增大,体积电阻率略有下降;击穿强度随含量增大而增大,含量为5 phr时,击穿强度达21.6 kV/mm,比纯HTV提高了26.3%;介电常数随SiO2中空微球含量增大先降低后升高,含量为2 phr时,介电常数最低;介电损耗随含量增大略有增大,但仍较低。SiO2中空微球/HTV复合材料电性能优于等含量气相SiO2/HTV复合材料。(2)研究了SiO2中空微球粒径对复合材料电性能的影响:279 nm SiO2中空微球/HTV复合材料具有较高的体积电阻率、较低的击穿强度和较低的介电常数,574 nm SiO2中空微球/HTV复合材料具有相对较低的体积电阻率和较高的击穿强度。(3)研究了408 nm SiO2中空微球和PS-SiO2实心微球对HTV电性能的影响:PS-SiO2/HTV复合材料具有较高的体积电阻率,但介电性能差,介电常数和介电损耗均高于SiO2中空微球/HTV复合材料。 |
英文摘要 | Electrical insulation protection is much important to ultra high voltage (UHV) and extra high voltage (EHV) transmission network which is considered as the backbone and core of smart grid. The composite insulators derived from high temperature vulcanized silicone rubber (HTV) as anti-pollution flashover are widely used in the transmission system due to its cheap price, better mechanical and water repellence performance, high flashover voltage and low density. However, the breakdown strength, volume resistivity and other key electrical insulation performances of HTV are not good enough for EHV and UHV power grid compared to electrical ceramics. In present thesis, submicron sized hollow silica spheres (HSS) were prepared and introduced into HTV to make the HSS/HTV composites. The effects of HSS on the mechanical properties, volume resistivity, breakdown strength and dielectric properties were characterized. The main research contents and results were summarized as followings:1. Preparation of HSSHSS with different particle sizes were prepared via a heterogeneous precipitation process of hydrolyzed silica species using polystyrene spheres as template. The HSS had amorphous structure and uniform sizes of 279 nm, 408 nm, 491 nm, 550 nm, 574 nm, with thin shell thickness of 10.9 nm, 10.3 nm, 11.9 nm, 16.4 nm, 12.4 nm and large specific surface area of 163 m2/g, 163 m2/g, 151 m2/g, 141 m2/g, 193 m2/g respectively.2. Mechanical performances of HSS/HTV composites(1) The effects of HSS (550 nm) contents: the tensile strength and elongation at break were improved with the increasing of the HSS contents. The tensile strength and elongation at break of 5 phr HSS/HTV composites were 1.35 MPa and 237%, which are higher than the 5 phr fumed silica/HTV composites.(2) The effects of HSS particle sizes: tensile strength of the the composites when filled with 5 phr HSS of 279 nm, 408nm, 491nm and 574nm was 0.97 MPa, 1.3 MPa, 1.26 MPa, 1.22 MPa, elongation at break, 189%, 208%, 207%, 205 % respectively.(3) The comparison of hollow structure and solid structure with same volume fraction: the tensile strength of 408 nm PS-SiO2/HTV composites was slightly reduced which is 1.17 MPa, compared to 408 nm HSS/HTV composies, which is 1.3 MPa.3. Electrical performance of the HSS/HTV composites(1) The effects of particle contents of HSS: volume resistivity of the HSS/HTV composites was improved to 1017 Ω?cm and then decreased slightly with the increasing of HSS contents; the breakdown strength increased with the HSS loading increasing. The composites containing 2 phr of HSS achieved a lowest relative permittivity. HSS/HTV composites showed better electrical performances compared to the fumed silica/HTV composites.(2) The effects of particle sizes of HSS: 279 nm HSS/HTV Composites represented higher volume resistivity, lower dielectric constant and breakdown strength; 574 nm HSS/HTV composites showed a relatively lower volume resistivity and higher breakdown strength.(3) The comparison of of hollow structure and solid structure with same volume fraction: volume resistivity of the 408 nm PS-SiO2/HTV composites was improved, however dielectric constant and dielectric loss properties was deteriorated compared to the 408 nm HSS/HTV composites. |
语种 | 中文 |
源URL | [http://ir.ipe.ac.cn/handle/122111/22919] ![]() |
专题 | 过程工程研究所_研究所(批量导入) |
推荐引用方式 GB/T 7714 | 钱西慧. SiO2中空微球/HTV复合材料制备与性能研究[D]. 北京. 中国科学院研究生院. 2016. |
入库方式: OAI收割
来源:过程工程研究所
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。