【作者】 王松；

【导师】 于志家；

【作者基本信息】 大连理工大学 ， 化学工程， 2014， 硕士

【摘要】 在金属表面上制备超疏水表面需同时具备粗糙结构和低表面能物质两个要素。本文选用生产生活中应用最为广泛的铝片作为基底,利用盐酸刻蚀在铝表面上得到微纳米混合粗糙结构,辅以不同低表面能物质修饰制得了铝基超疏水表面。制得的表面最高接触角达到159°,滚动角低至3.5°。对固体表面的疏水性分析,往往也从粗糙结构和低表面能物质两个方面入手。在已有的研究基础上,本文重点关注了低表面能物质对疏水性的影响。通过对比分析用来修饰表面的低表面能物质,如本文所用的氟硅烷、月桂酸、聚四氟乙烯,发现材料表面的疏水性不仅与低表面能物质上的疏水基的本性有关,还与低表面能物质在固体表面的排列状态和紧密程度相关。低温环境下,利用加湿器产生微米级“水雾”来模拟结霜条件,观测超疏水铝表面与普通铝表面上的结霜情况。实验发现,在温度高于-15℃时,超疏水铝表面能够推迟结霜30-60min,但其表面上的结霜量多于普通铝表面；温度低于-15℃后,两种表面同时出现霜晶,但超疏水表面上的结霜量显著低于普通表面上的结霜量。本文还在-5℃和-10℃下进行了超疏水铝表面和普通铝表面上的结冰实验。利用喷雾瓶向两种表面间隔性地喷洒毫米级液滴,实验表明,超疏水铝表面上的结冰量一直低于普通铝表面。同时还发现,喷洒到超疏水铝表面上的水呈液滴状,难以冻结；而喷洒到普通铝表面上的水迅速铺展成一层水膜,低温下快速冻结。为比较两种不同表面除冰的难易程度,本文还进行了冰块附着力测试实验。-20℃下,将超疏水铝片和普通铝片都放入圆柱形模具内,注入相同水量,冻结2h。将两片铝片从模具中取出后,夹在离心装置上,测试冰块从铝片表面脱离时的离心力,即冰块在铝片上的附着力。实验结果显示,冰块在超疏水铝表面上的附着力仅为普通铝表面上的1/3。更多还原

【Abstract】 Roughness and low surface energy materials are two basic elements in preparation of super-hydrophobic surface on metals. This paper chose the most widely used aluminum as the base and prepared super-hydrophobic surface via chemical etching following modified with different low energy materials. The water contact angle of the surface can be up to159°and the contact angle hysteresis can be as low as3.5°The hydrophobicity analysis of the solid surface often starts with roughness and low surface energy materials. Based on the previous research, this article focused on the impact of low surface energy. Through comparison of the low surface energy materials used to modify the surface, as used herein, fluorosilane, lauric acid, polytetrafluoroethylene, we found that the hydrophobicity of the surface is not only related to the characteristic of hydrophobic groups, but also to the arrangement of the hydrophobic groups.At low temperatures, frost experiment was carried out on the super-hydrophobic aluminum surface and common aluminum surface with humidifier to produce micron water droplets. It was found that the super-hydrophobic aluminum surface can postpone frost for30-60min even though the amount of frost on the surface was more than ordinary aluminum surface when the temperature is higher than-15℃. While the temperature is below-15℃,both of the two surfaces start frosting simultaneously.However, the amount of frost on the super-hydrophobic aluminum surface significantly lower than that on the common aluminum surface.In this paper, freezing experiments were also carried out on super-hydrophobic surface and common aluminum surface at-5℃and-10℃respectively. We found that the amount of ice on super-hydrophobic aluminum surface was less than that on common aluminum surface. It was also found that the sprayed water on super-hydrophobic surface was droplet-shaped and hard to freeze while the water formed a water film that can be frozen quickly on common surface.This paper also carried out ice-adhesion test experiment to compare the capability of deicing of the two surfaces. Place the super-hydrophobic aluminum surface and common aluminum surface into the cylindrical molds separately, then pour same amount of water into them and then freeze for2hours at-20℃. Remove the two sheets of aluminum from the molds and clip them on the centrifuge device. We can calculate the ice-adhesion force on the different aluminum surfaces using the centrifugal force when the ice detach from the surface. Experimental results showed that the adhesion of ice on the super-hydrophobic aluminum surface is only1/3of the common aluminum surface.更多还原