共查询到20条相似文献,搜索用时 46 毫秒
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通过电化学刻蚀和自组装两步法,在铜箔表面成功制备了一层超疏水薄膜。薄膜表面与水的接触角可达到160°。用扫描电镜对超疏水表面进行了表征分析。扫描电镜对铜箔表面观察显示,该表面存在微米.纳米尺度的双层复合结构:底层为均匀分布的沟壑状凹槽,在其表面分布了类草坪状的氧化铜纳米颗粒。研究显示双层的微纳米复合结构是在铜箔表箍形成超疏水的关键因素。 相似文献
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采用两步喷涂法制备了经疏水修饰的二氧化硅(R974)/有机硅树脂(GC-500Z)超疏水复合涂层。通过接触角测定仪和扫描电子显微镜研究了R974的含量及其喷涂时间、GC-500Z的喷涂时间对涂层最终疏水性的影响。结果表明,涂层最终的疏水性是由其表面是否形成沟壑以及所形成的沟壑中的R974的含量所决定。当表面形成比较明显的沟壑且沟壑中的R974含量比较低时,涂层表现为一种水滴无法滚动离开表面的疏水状态;如果沟壑中的R974含量比较高并没有明显的沟壑形成,则涂层表现为一种水滴非常容易滚动离开表面的超疏水状态。 相似文献
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非金属超疏水材料的制备方法及研究进展 总被引:1,自引:0,他引:1
介绍了构造超疏水材料的基本原理,综述了近年来超疏水材料的制备方法,重点介绍了构造表面微纳米粗糙结构的方法(刻蚀法、相分离法、模板法、化学液相沉积法、溶胶凝胶法),并讨论了不同制备方法的优缺点和应用前景。用激光辐照、等离子体刻蚀等方法处理非金属材料都能得到理想的微纳米结构;用激光刻蚀低表面自由能的聚合物材料,可以不用修饰直接得到超疏水表面;相分离法适用于制备超疏水聚合物薄膜,其优点是设备简单,成本低,适合大规模制造;利用模板压印法制备聚合物超疏水材料简单易行,利用剥离力和反模板的作用,可以形成理想的二阶微纳米粗糙结构。 相似文献
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Paper-based materials are widely used in various fields due to their advantages, such as environmental friendliness and sustainability. However, the highly hydrophilic nature of the cellulose that makes up paper-based materials limits their use. In this paper, micron/nano-graphite/polydimethylsiloxane (PDMS) coatings with excellent superhydrophobic and conductive properties were prepared on the surface of filter paper by a simple spraying method. A mixture of micro-graphite and nano-graphite was used to form a multistage rough structure on the surface of the filter paper by spraying, and the low surface energy PDMS enhanced the adhesion of the micro-graphite and nano-graphite on the surface of the filter paper. The results showed that the samples possessed the best superhydrophobic properties when the ratio of micro-graphite to nano-graphite was 1:1, at which time the contact and rolling angles of the samples were 165.4° and 3.2°, respectively. The prepared superhydrophobic samples have good bounce and self-cleaning properties, while the samples have good mechanical stability and chemical resistance. Additionally, due to the conductivity of micro–nano-graphite, both particle sizes closely contact the sample surface, creating a conductive network. With a 1:1 ratio of micro- and nano-graphite, the coating exhibits minimal resistance at 1.89 KΩ, and the sample maintains stable conductivity even underwater. The above properties greatly extend the application range of paper-based superhydrophobic materials. 相似文献
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利用硬脂酸钠(NaSt)和油酸钠(NaOL)对文石型和方解石型两种CaCO3粉体进行表面改性,将改性的CaCO3粉体与聚二甲基硅氧烷(PDMS)共混,喷涂得到了CaCO3/PDMS基超疏水涂层。采用XRD、SEM、接触角测量仪对改性CaCO3粉体及超疏水涂层进行测试,考察了不同晶型CaCO3用量对涂层疏水性能的影响,并对超疏水涂层的自清洁性及稳定性进行了评价。结果表明,当NaSt和NaOL用量分别为反应体系CaCO3理论生成质量的5%时,CaCO3粉体改性效果最好,所制备的CaCO3/PDMS涂层疏水性最佳。当CaCO3和PDMS质量比为1.5∶1时,CaCO3/PDMS涂层接触角>150°,具有超疏水性。玻璃板涂层表面的亚甲基蓝污染物可以完全随着液滴被冲走,没有残留,且经过500 m L流速5 m/s的水流冲击,接触角仍达140°以上。 相似文献
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单宁酸磷酸酯的合成及其抗氧化性能评价 总被引:1,自引:0,他引:1
以单宁酸为原料、三聚磷酸钠为磷酰化试剂、尿素为催化剂进行磷酸化反应合成单宁酸磷酸酯。通过正交实验优化最佳合成工艺,并利用磷含量计算产率,通过傅里叶红外光谱(FT-IR)、紫外光谱(UV)表征其结构。研究了单宁酸磷酸酯的电导性,并利用其对羟基自由基(·OH)和超氧阴离子自由基(·O_2~-)的清除能力评价了抗氧化性能。结果表明,最佳合成工艺条件为n(单宁酸)∶n(三聚磷酸钠)=1∶1、反应时间为18 h、反应温度为65℃,在此条件下的产率可达86.02%。产物的电导率与其质量浓度呈显著正相关,并在一定浓度下电导率比相应单宁酸高出10~15倍;当质量浓度为1 g/L时,产物与单宁酸对·OH和·O_2~-清除率分别为75%和55%。结果证明,在优化的最佳条件下产率较高,所合成的单宁酸磷酸酯具有较好的抗氧化活性。 相似文献
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在由五倍子提取的单宁酸中,通常存在着一定量的焦性没食子酸,采用乙腈、四氢呋喃和水在pH值为3的条件下利用Luna C18色谱柱可以很好地将焦性没食子酸与单宁酸中其它组分分离,并测定焦性没食子酸含量,该方法简单可行,已应用于工业生产. 相似文献
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硬脂酰单宁酸酯的合成及抗氧化作用 总被引:4,自引:0,他引:4
以单宁酸和硬脂酰氯为原料合成了一种油溶性抗氧化剂硬脂酰单宁酸酯 (C18 TA)。探讨了硬脂酰氯和单宁酸的量比、催化剂对甲苯磺酸的用量、反应温度和溶剂等对合成的影响。确定了较佳的反应条件 :n(单宁酸 )∶n(硬脂酰氯 ) =1∶2 0 ,m(单宁酸 )∶m(催化剂 ) =1 0 0 :0 .0 3 ,二氧六环作溶剂 ,反应温度 10 0~ 10 2℃ ,氮气保护下反应 4h。C18 TA在菜籽色拉油中的含量为6 0 0mg/kg时 ,6 0℃强制氧化 18d ,其POV抑制率可达 6 6 0 % ,明显高于相同条件下BHT的POV抑制率 5 6 0 % 相似文献
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Panagiotis Dimitrakellis Kosmas Ellinas Georgia D. Kaprou Dimitrios C. Mastellos Angeliki Tserepi Evangelos Gogolides 《大分子材料与工程》2021,306(4):2000694
The use of antibacterial surfaces is an effective way to reduce exposure to pathogens and therefore infections. Several methods to fabricate antibacterial surfaces using surface modification methods as well as a bactericidal agent incorporation inside materials have been reported. However, in most cases the factors affecting the antibacterial behavior of a surface are not discussed in detail. Here, a comparative study on the antibacterial properties of surfaces with different characteristics against Gram-negative bacteria (Escherichia coli) under dynamic conditions is presented, aiming to unravel the interplay among the most important factors when realizing an antibacterial surface, that is, surface morphology, wetting properties, and the use of a bactericidal agent. Significant bactericidal efficacy for the micro-nanotextured, superhydrophilic surfaces is demonstrated, possibly due to a mechanical killing induced by the interaction of bacteria with the micro-nanotopography. On the other hand, superhydrophobic surfaces without any bactericidal agent exhibit low interaction with the bacteria containing medium and therefore lower bactericidal action, whereas superhydrophobic surfaces with a bactericidal agent exhibit extreme non-wetting properties and rapid bactericidal effect through release of Cu particles. Finally, the role of the hydrophobic coating as barrier against uncontrolled release of the bactericidal agent when deposited as top layer is also showcased. 相似文献
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五倍子提取单宁酸的工艺研究 总被引:2,自引:0,他引:2
从五倍子中提取单宁酸,通过正交实验优化筛选出最佳工艺.1∶7料液比,60 ℃浸提取6次,每次1 h.单宁酸的提取收率可达50%以上,含量达到90%以上. 相似文献