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氟化(甲基)丙烯酸酯聚合物是一类新型的低表面能材料,它的氟化链段使其具有优异的疏水疏油性能,而非氟化(甲基)丙烯酸酯链段则赋予了其良好的溶解性和相容性。通过设计和控制氟化(甲基)丙烯酸酯聚合物的结构可改变聚合物表面润湿性。本文综述了影响氟化(甲基)丙烯酸酯均聚物、无规共聚物、嵌段共聚物、接枝共聚物、核壳共聚物和交联网状共聚物表面润湿性的因素,通过分析聚合物的结晶度、表面元素含量、表面能和接触角讨论了聚合物结构与表面润湿性及润湿稳定性之间的关系,并给出了相关模型,为今后设计合成具有稳定表面润湿性的氟化(甲基)丙烯酸酯聚合物提供了理论依据和指导。 相似文献
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微/纳米结构的导电聚合物由于具有高导电性、易合成以及优异的环境稳定性从而在许多先进的研究领域备受关注,并有望在分子导线、化学和生物传感器、发光器件等领域获得广泛应用。 特别是,复杂的三维自组装结构在获得高性能和功能化的材料方面提供了巨大的潜在应用价值。本文主要介绍了我们利用胶束的软模板和自组装驱动力的协同效应,实现由一维纳米结构组装的三维微米结构导电聚合物方面的研究进展。该制备技巧在于低表面自由能的含氟有机酸具有软模板、掺杂剂、自组装驱动力,以及诱导超疏水性的多重作用实现导电聚合物三维结构的组装和多功能化。介绍了利用环境湿度调整分子的自组装驱动力,实现导电聚合物由一维纳米结构向三维微米结构的组装。此外,还介绍了利用导电聚合物可逆的化学掺杂/脱掺杂机制,实现导电聚合物表面浸润性的可逆转化。最后介绍了在液/液/固三相体系中,通过外加电场刺激,可实现油滴在导电聚合物表面的浸润性和黏附力的控制。 相似文献
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采用溶胶-凝胶法制备不同粒径SiO2粒子,通过表面改性得到不同形状复合粒子,并利用氟硅氧烷的表面自组装功能制备了具有“荷叶效应”的超疏水涂膜。通过原子力显微镜、扫描电镜和水接触角的测试对膜结构及性能进行了表征,探讨了SiO2粒子的粒径和形状与表面微观结构、表面粗糙度和表面疏水性能的关系。结果表明含单一粒径粒子涂膜表面水接触角符合Wenzel模型,而复合粒子构成了符合Cassie模型的非均相界面;单纯的粗糙度因子不能反映水接触角的变化,复合粒子在膜表面的无规则排列赋予涂膜表面不同等级的粗糙度,使得水滴与涂膜表面接触时能够形成高的空气捕捉率和较小的粗糙度因子;其与在涂膜表面能形成自组装分子膜的氟硅氧烷共同作用赋予了涂膜超疏水性能,而这种超疏水性能与复合粒子的粒径大小和形状基本无关。 相似文献
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Tyrosine-derived polycarbonates having carboxylic acid pendant groups were characterized by water contact angle and X-ray photoelectron spectroscopy (XPS). A pronounce decrease of receding angle as well as contact angle hysteresis as a function of acid composition strongly indicated that the acid groups are more accessible at the water/polymer interface after hydration. pH dependent contact angle confirmed an existence of carboxylic acid groups in the surface region. The receding angle transition appearing in the pH range of 4-6 was a consequence of hydrophilicity change due to interconverting from carboxylic acid (-COOH) to carboxylate ion (-COO−). The surface compositions of imidazole-labeled polymers as analyzed by XPS were consistent with the bulk stoichiometry of the polymers. Reactivity of acid groups towards chemical reaction at the surface was also investigated. The acid groups at the surface of polymers were capable of adsorbing a significant amount of calcium ion from simulated body fluid and being activated by a reaction with N-hydroxysuccinimide. 相似文献
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用微干涉测量技术直接测定楔压等温线,研究了电解质浓度对阳离子表面活性剂TTAB在浓度大于cmc时形成黑膜厚度的影响及膜表面张力与溶液表面张力之间的差别.结果显示,黑膜厚度取决于楔压和电解质浓度,随着楔压的增加,液膜厚度减少至一定程度后几乎保持不变,表明黑膜类型的转化是阶跃式的,而电解质屏蔽了液膜两个表面电荷层间的排斥作用,故电解质浓度增加,液膜厚度变小.由楔压等温线得出的膜表面张力的结果说明一般黑膜的表面张力与溶液的表面张力并无明显差别. 相似文献
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蚊子体表面的微纳米结构与浸润性 总被引:1,自引:0,他引:1
通过光学显微镜及自行设计的接触角测试系统研究了成蚊体表面(如翅膀、 复眼)的浸润行为, 发现了不同的体表面由于不同的生物功能而具有不同的超疏水特性. 通过扫描电子显微镜检测成蚊翅膀和复眼表面, 揭示了分布在成蚊体表面上的不同的微观结构形貌, 另外, 微米结构表面上还包含了纳米结构是其体表面微观结构的共同属性. 因此, 微纳米等级结构与浸润性之间存在重要的依赖关系. 相似文献
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Zwitterionic polymers are important in a wide range of industrial, biological and medical fields. Their chemical structures include an equal amount of anion and cation groups, and such structures give rise to many unique functionalities, such as temperature response, anti‐polyelectrolyte effect, and strong hydration properties. In this review, we focus on the structures and applications of functional zwitterionic polymers on surfaces. We review three areas of applications according to the architecture of the polymeric systems: surface coating, complex solutions, and hydrogel. We review the simulation and theory work and highlight some outlooks for further development. 相似文献
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纳米通道内表面浸润性对气泡的作用 总被引:2,自引:0,他引:2
运用分子动力学模拟方法研究了在质量力驱动下不同浸润性壁面纳米通道中气泡的分布及其运动状况, 提出了一种统计纳米通道中气泡运动速度的方法. 结果显示, 在亲水性壁面的纳米通道中, 气泡位于通道中间, 气泡的运动速度接近但小于通道中心流速, 在势能强度较大时, 壁面吸附的分子较多, 气泡也较大, 反之则气泡较小; 对超疏水性壁面, 气泡则位于固壁附近, 两个壁面形成对称的一对气泡, 气泡的运动速度接近但大于边缘速度. 流体总的流动速度随着流体粒子与壁面粒子作用的减弱而增大, 滑移速度则逐渐从负转变为正. 相似文献
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紫外光谱研究表明,AZ正性光胶当厚度大于10μm时,在200~285nm的紫外光区几乎不透光。本研究据此研制了一种以固化后的AZ光胶做挡光层、石英玻璃做底板的紫外光刻掩膜。应用AZ光胶掩膜对聚碳酸酯(PC)表面进行以低压汞灯(主要辐射254nm紫外光)为光源的选择性光化学改性,在光照区域形成化学镀所需的催化中心后,采用化学镀技术,在PC毛细管电泳芯片上制备安培检测用的集成化金微电极。本掩膜材料简单,制作方便,无须洁净实验室和贵重的设备,成本低廉。 相似文献
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Polyacrylonitrile fibers were treated with a nitrogen glow-discharge plasma. The surfaces of untreated and treated fibers were examined with contact angle measurements, atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). Surface energy calculations of the fibers were carried out from contact angle measurements using the relationships developed by Fowkes. It is found that plasma treatment causes a reduction in water contact angle on the fiber surfaces. The dispersion component of surface energy changes slightly, while the polar component is increased significantly from 14.6 mN/m to 58.7 mN/m and the total surface energy increase is 139%. The increase of surface energy is mainly caused by the introduction of hydrophilic groups on the fiber surfaces after plasma treatment. 相似文献
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Ana Sánchez-Grande Dr. José I. Urgel Aleš Cahlík Dr. José Santos Shayan Edalatmanesh Eider Rodríguez-Sánchez Dr. Koen Lauwaet Dr. Pingo Mutombo Prof. Dana Nachtigallová Reed Nieman Prof. Hans Lischka Dr. Bruno de la Torre Prof. Rodolfo Miranda Dr. Oliver Gröning Prof. Nazario Martín Prof. Pavel Jelínek Prof. David Écija 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(40):17747-17752
We report on the synthesis and characterization of atomically precise one-dimensional diradical peripentacene polymers on a Au(111) surface. By means of high-resolution scanning probe microscopy complemented by theoretical simulations, we provide evidence of their magnetic properties, which arise from the presence of two unpaired spins at their termini. Additionally, we probe a transition of their magnetic properties related to the length of the polymer. Peripentacene dimers exhibit an antiferromagnetic (S=0) singlet ground state. They are characterized by singlet–triplet spin-flip inelastic excitations with an effective exchange coupling (Jeff) of 2.5 meV, whereas trimers and longer peripentacene polymers reveal a paramagnetic nature and feature Kondo fingerprints at each terminus due to the unpaired spin. Our work provides access to the precise fabrication of polymers featuring diradical character which are potentially useful in carbon-based optoelectronics and spintronics. 相似文献
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Hartley Patrick G. Thissen Helmut Vaithianathan Tharshan Griesser Hans J. 《Plasmas and Polymers》2000,5(1):47-60
A method for the determination of coating film thicknesses at nanometer resolution based on surface masking and atomic force microscopy (AFM) is described. A polymeric mask is used to cover part of a substrate during the deposition of thin polymeric coatings by plasma polymerization, allowing the production of well defined polymer steps of heights of a few tens of nanometers. Tapping mode AFM has been employed to analyze the topography of these steps at high resolution. This method has also allowed accurate measurement of the kinetics of the deposition of plasma polymer films over a range of exposure times. XPS analysis of different substrate surfaces following mask removal found barely detectable residues, suggesting that the underlying surface chemistry remains unchanged, and accessible for further modification. In combination with quartz crystal microgravimetry, the method has been applied to the measurement of the density of plasma polymer coatings in the thickness range 4–50 nm. 相似文献
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微纳结构超疏水表面的浸润性分析及设计 总被引:1,自引:0,他引:1
微纳复合结构超疏水表面在防污、流动减阻、防冰等领域具有广阔的应用前景,超疏水表面主要通过设计表面化学性质和微观几何结构来获得.合理设计保持表面润湿态的稳定性是其性能发挥的关键.以"液滴-超疏水表面"系统为研究对象,基于最小能原理分析了四种稳定润湿形态,指出影响润湿状态的本征接触角和微观结构参数(相对柱距、相对柱高).推导了本征接触角的计算公式并对常见材料的本征接触角进行了讨论.结合四种润湿态方程,绘制了随着相对柱距和相对柱高的润湿云图,并将润湿云图归纳为"一点三线六区四状态".分析了相对柱距和相对柱高对浸润状态的影响,结果表明较大的本征接触角、较小的相对柱距和较大的相对柱高能够减小浸润状态发生转变的临界参数,从而拓展超疏水表面的区域范围,有利于超疏水表面的稳定性.利用文献数据验证了上述润湿云图能够准确反映出润湿形态.在上述工作基础之上总结提炼了超疏水表面设计的一般思路.研究结果可为超疏水表面的设计提供理论依据和技术基础. 相似文献
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Cristofor Simionescu Severian Dumitriu Marcel Popa Cristina Coman Vlad Artenie 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(6):677-686
Pepsin was immobilized on BIOZAN R (Hercules) with dicyclohexylcarbodiimide as activator. The reaction product obtained has a protein content of 35–110 mg/g of polymer and a proteolytic activity between 20.85–28.75 μmol tyrosine/L·min·g of polymer). The coupling reaction rate is maximum under the following conditions: pepsin/BIOZAN R ratio = 0.52 g/g, DCCI/BIOZAN R ratio = 0.2 g/g, pH = 3.4, reaction time = 4 h. 相似文献