交流电晕对超疏水及普通硅橡胶憎水性的影响

复合绝缘子优异的防污闪性能主要得益于硅橡胶材料表面的憎水性及其迁移特性。在近几年有关表面和界面的研究中,超疏水材料以其优异的超级憎水性和自清洁特性引起了电力行业研究人员广泛的关注。静态接触角大于150°,滚动角小于10°的材料表面被称之为超疏水表面。以往的研究表明,电晕放电是造成硅橡胶表面憎水性下降乃至丧失的主要因素之一。文中以自制的2种超疏水表面硅橡胶和1种普通表面硅橡胶为研究对象,开展了交流电晕对其憎水性及憎水恢复特性的影响研究。考虑到电晕后硅橡胶表面的滚动角会大于90°,文中用接触角滞后取代滚动角表征表面的自清洁能力。试验结果表明:普通硅橡胶表面的静态接触角和接触角滞后分别是113.2°和11.7°,而模板法制备的2种具有微观表面结构的硅橡胶的静态接触角均大于150°,接触角滞后均小于3°,具有良好的超疏水特性及自清洁特性;在电晕处理硅橡胶表面后及电晕后恢复的过程中,普通表面硅橡胶的憎水性及自清洁特性都明显不如超疏水表面硅橡胶;而对于两种超疏水表面,封闭式结构μc表面的憎水性及其恢复特性要优于开放式结构μ_o表面。

Influence of AC Corona on Hydrophobicity of Silicone Rubber with Superhy Drophobicor Normal Surface

Two types of superhydrophobic high-temperature vulcanized(HTV)silicone rubbers(SRs)and a normal HTV SR were prepared to investigate the influences of corona discharge on their hydrophobicity and recovery.Considering the rolling angle of SR surface is greater than 90°after corona treatment,the contact angle hysteresis is substituted for it to represent the self-cleaning property of SR surface.Test results show that the static contact angle and contact angle hysteresis of the normal SR before corona treatment are 113.2°and 11.7°,respectively.While both superhydrophobic SRs with micro-structure surface have the static contact angle of larger than 150°and contact angle hysteresis of smaller than 3°,which means they have excellent superhydrophobicity and self-cleaning property.The hydrophobicity and self-cleaning property of normal SR are obviously inferior to those of superhydrophobic SRs after corona treatment or in the process of recovery.For the two types of superhydrophobic SRs,the hydrophobicity and recovery property of the surface with closed-architecture structure are superior to those of the surface with open-architecture structure.