【作者】 徐飞鹏；

【导师】 王大政；

【作者基本信息】 哈尔滨工业大学 ， 船舶与海洋工程， 2016， 硕士

【摘要】 船舶与海洋平台等海洋结构物在海洋环境中工作时,难免受到腐蚀及海洋污损物的附着。海洋生物附着一方面会影响结构物的正常工作,增加上坞维护费用;另一方面会使自重增加,航行时摩擦阻力显著提高,增加燃油费用。通过涂覆仿生疏水复合涂层可以有效地抑制腐蚀及生物污损附着,且具备良好的减阻性能。仿生疏水复合涂层的制备主要有两点:一是低表面能;二是微观粗糙结构。因此,本文工作主要分为以下三部分:(1)CNT-OH/氟硅树脂仿生疏水复合涂层的制备及研究以氟硅树脂作为低表面能成膜物,以碳纳米管(CNT)为纳米填料来构建微观粗糙结构,通过对碳纳米管种类、含量的研究制备具备一定疏水性的CNTOH/氟硅树脂仿生疏水复合涂层。复合涂层的接触角、滚动角及表面能分别达到121°、21°、4.28m N/m;且具有一定耐盐雾腐蚀和疏水稳定性,在25d盐水浸泡试验后,复合涂层的接触角仍大于95°,吸水率为0.59%。其物理性能优良,铅笔硬度为5H,附着力为0级,且在320℃以下时具有较好的耐热稳定性。(2)CNT-OH/改性硅溶胶仿生疏水复合涂层的制备及研究利用正硅酸乙酯水解-凝胶法制备硅溶胶,并添加硅烷偶联剂六甲基二硅胺(HMDS)进行改性,制备得到了具备一定疏水性能的改性硅溶胶。将改性硅溶胶、CNT-OH、水及少量的丙烯酸树脂球磨机混合处理,喷涂后固化形成复合涂层。选用HMDS和1H,1H,2H,2H-全氟癸基三乙氧基硅烷(FTES)作为表面改性剂,制备得到CNT-OH/改性硅溶胶仿生疏水复合涂层。仿生复合涂层疏水自清洁性能优异,接触角/滚动角分别为145°/15°,表面能仅有0.595m N/m。25d盐水浸泡试验后,复合涂层的接触角仍大于122°,吸水率为0.37%。复合涂层具有良好的物理性能,其铅笔硬度为5H,附着力为0级,且在1000℃以下时具有良好的耐热稳定性,失重率仅有12%。制备最佳工艺条件为:硅溶胶:CNTOH=20:1,丙烯酸添加量为硅溶胶的30%,选用FTES作为表面改性剂,添加量0.8g(10ml乙醇中)、表面改性时间为2h。(3)平板阻力测试系统设计及仿生疏水复合涂层减阻性能研究自行设计小量程平板阻力测试系统,并在不同流速下进行了几种仿生疏水复合涂层的阻力性能测试。首先通过对阻力测试系统的标定,分析试验架平衡度和试验板重量对数据的重复性和稳定性的影响,并得到试验板受力与应变片的应变之间的线性关系,斜率为8.9227。随后对不同复合涂层进行阻力性能测试,相对于粗糙平板,市场购买的环氧漆涂层减阻率为5.2%,CNT-OH/氟硅树脂复合涂层减阻率为6.8%,CNT-OH/改性硅溶胶复合涂层减阻率为11.5%。复合涂层的减阻机理是涂层的低表面能性能及其表面存在微观粗糙结构共同作用的结果。更多还原

【Abstract】 It is difficult to avoid corrosion and adhesion of marine fouling when marine structures such as ships and platforms work in the marine environment. And Adhesion of marine fouling can not only affect the normal work of structures, increasing maintenance costs on the dock, but also increase the weight and the frictional resistance when a ship sails, resulting in a rising fuel consumption and a waste of resources. Applying some biomimetic and hydrophobic composite coatings is effective in inhibiting corrosion, fouling attachment and improving the drag-reduction property. Therefore, this paper is divided into three parts as follows when the low surface energy and the microscopic roughness are mainly involoved in the preparation of the biomimetic and hydrophobic composite coatings.Firstly, the fluorine-silicone resin(FSR) was choosen as the film-forming composition with a low surface energy, and a micro-rough structure was built with hydroxy carbon nanotubes(CNT-OH) nano-filler, then the biomimetic and hydrophobic CNT-OH/FSR composite coating was prepared with different kinds and amounts of carbon nanotubes. The contact angle, sliding angle and the surface energy of the composite coating were 121°, 21° and 4.28 m N/m respectively. The composite coating has an excellent corrosion resistance and a stable hydrophobicity when its contact angles remained above 95° and the water absorption was 0.59% after the salt immersion test for 25 days. And the coating had excellent physical properties with the pencil hardness and adhesion of 5H and level 0 respectively and it had a good heat stability below 320℃.Secondly, modified silica sol with some hydrophobicity was prepared via a sol-gel method when tetraethoxysilane(TEOS) hydrolyzed and a silane coupling agent hexamethyldisiloxane amine(HMDS) was simultaneously added. Then the modified silica sol, CNT-OH, water and a small amount of an acrylic resin were mixed by using a ball mill, and the composite coating was prepared by a spaying method and a curing treatment. 1H,1H,2H,2H-Perfluorodecyltriethoxysilane(FTES) and HMDS were selected as the surface modifying agent and the biomimetic and hydrophobic CNTOH/ modified silica sol composite coating was prepared. The biomimetic and hydrophobic composite coating has excellent self-cleaning properties with the contact angle and sliding angle of 145°and 15° and the surface energy of 0.595 m N/m. The composite coating has an excellent corrosion resistance and a stable hydrophobicity when its contact angles remained above 122° and the water absorption was 0.37% after the salt immersion test for 25 days. And the coating had excellent physical properties with the pencil hardness and adhesion of 5H and level 0 respectively and it had a good heat stability below 1000℃. The optimum conditions were that the mass ratio of silica sol and hydroxyl carbon nanotubes was 20 with the acrylic acid added in an amount of 30% silica sol. FTES was chosen as a preferable surface modifier when the amount added was 0.8g(in 10 ml ethanol) and the surface modification time was 2h.Thirdly, the drag-reduction properties of the biomimetic and hydrophobic composite coatings were measured by a self-designed flat plate resistance test system with a small scale. Some conclusions were obtained after calibrating the test system. The data obtained with a good repeatability and stability met the test requirements under different equilibrium conditions and weights of the plate. And there was a linear relationship between the force of the test plate and the strain of strain gauges with a slope of 8.9227. Excellent drag-reduction properties were achieved in different biomimetic and hydrophobic composite coatings, when the drag reduction rate of the epoxy resin composite coating from the market purchase, the CNT-OH/FSR composite coating and the CNT-OH/modified silica composite coating were 5.2%, 6.8% and 11.5% respectively compared to the rough plate. The drag-reduction results are attributed to the low surface energy and the microscopic roughness of the biomimetic and hydrophobic composite coatings.更多还原