接触角

Abstract(#br)This paper describes rapid, simple, and cost-effective treatments for producing biocompatible and long-term hydrophilic polydimethylsiloxane (PDMS) surfaces identified in an experimental study investigating 39 treatments in all. The wetting of the surfaces was monitored during six months. Changes in surface morphology and chemical composition were also analyzed. Some of the treatments are presented here for the first time, while for earlier presented treatments the selection of investigated parameters was wider and the observation period for the surface wetting longer.

Abstract(#br)A novel and facile avenue was developed to successfully fabricate a regular hierarchical surface structure on a copper sheet via the combination of polydimethylsiloxane (PDMS) template and chemical etching method in this paper. The as-prepared hierarchical surface structure was comprised of uniform-sized microprotrusions and nanostructures which was similar to the natural lotus leaf. After modified by stearic acid, the surface was covered with a layer of hydrophobic chemical groups and became superhydrophobic.

Abstract(#br)Fabrication of microscale surface structures is a promising method for controlling the surface wettability of materials. Herein, the micropillar and microhole arrays of polydimethylsiloxane (PDMS) were fabricated through a soft lithography process, and the modified wettability was investigated. Using PDMS samples with different degrees of crosslinking, a PDMS–PDMS pattern transfer was achieved, and the microhole and micropillar arrays were obtained from a single master substrate.

Abstract(#br)This study investigates the triboelectric energy harvesting phenomenon of falling water droplets on a novel nanocomposite surface, chemically synthesized from reduced graphene oxide (rGO) and polydimethylsiloxane (PDMS) polymer. The prime concern of this work is to synthesize such a triboelectric nanocomposite film, which will pose optimized hydrophobicity along with ameliorated dielectric properties through proper optimization of filler quantity inclusion in PDMS matrix.

Fabrication method of PDMS microlensesusing water-based molding methodPDMS;microlens;contact angle;surface modification;This paper reports a new fabrication method of polydimethylsiloxane (PDMS) microlenses with various curvatures by using a water-based mold. The hydrophobic surface of Polypropylene (PP) substrate was modified by corona discharge using tesla coil to have hydrophilic surface. Then hydrophilic surface of PP substrate takes hydrophobic recovery to have various contact angles from less than $25^{\\circ}$ to about $84^{\\circ}$.

Surface Modification of Polydimethylsiloxane using Nd:YAG LaserPDMS;Surface modification;Nd:YAG laser;Contact angle;Nd:YAG($\\lambda$=266 nm, pulse) laser beam was irradiated on the PDMS surface to improve its chemical reaction, wettability, adhesive property. The various surface modification methods of PDMS were already studied using oxygen plasma, ozone and corona discharge. The surface modification using laser has the advantage of the simple experiment that only directly irradiated laser beam on the PDMS surface in the air.

利用PDMS对AZ31B镁合金表面的双工MAO / DLC涂层进行改性，开发了一种可靠、高性能的涂层工艺。首先，采用MAO和非平衡磁控溅射相结合的工艺制备了双工MAO / DLC涂层。随后，采用PDMS溶液对MAO / DLC涂层进行改性，采用传统的浸涂法。通过SEM、CA、Raman光谱、摩擦磨损性能、极化曲线和NSS试验，评价涂层试样的表面特征、结合强度、硬度、摩擦学性能和耐腐蚀性能。PDMS改性使MAO / DLC涂层的HIT从15.96   GPa降低到8.34   GPa，这是由于PDMS具有良好的流变性能，在MAO / DLC涂层上形成了粘弹性Si基有机聚合物层。但PDMS改性的MAO / DLC涂层较MAO-和MAO / DLC涂层样品致密、疏水性强，结合强度更高。而且PDMS改性降低了MAO / DLC复合涂层的COF和磨损率。这表明，由于PDMS的Si-O网络引入了转移的Si氧化物，以及DLC层在滑动过程中的低石墨化，PDMS改善了摩擦学性能。此外，PDMS改性10   min的MAO / DLC涂层试样的腐蚀电流密度与MAO / DLC涂层试样相比降低了2个数量级，与裸基体相比降低了5个数量级。NSS试验证明PDMS层减缓了镁合金在长期服役下的腐蚀，增强了腐蚀防护效率。

最常见的有机硅聚合物——聚二甲基硅氧烷( PDMS )的许多应用都是由于其疏水性质的结果。这种行为的关键量是水与水滴的接触角、聚合物的表面张力及其与水的界面张力。这些量综述了PDMS和氟硅聚甲基三氟丙基硅氧烷( PMTFPS )以及其他一些较不常见、氟化程度较高的氟硅。由于脂肪族氟碳化合物通常被引入聚合物以降低表面张力，所以PMTFPS的表面张力高于PDMS是出乎意料的。然而，这一观察与Zisman早期的广泛研究是一致的。也有些令人惊讶的是，没有确定的水与PDMS的接触角和PDMS /水界面的界面张力值。对此进行了一些原因探讨，并考虑了相关的局限性。PDMS表面能够呈现的多种方式必然对所报道的水接触角范围产生重大影响。

最熟悉的有机硅聚合物聚二甲基硅氧烷( PDMS )的许多应用都是其疏水性质的结果。这种行为的关键因素是与水滴的水接触角、聚合物的表面张力以及与水的界面张力。综述了聚二甲基硅氧烷( PDMS )和氟硅聚甲基三氟丙基硅氧烷( PMTFPS )以及其他一些较不常见、较高氟化的氟硅。由于脂肪族氟碳化合物通常被引入到聚合物中以降低其表面张力，所以PMTFPS的表面张力比PDMS高得出人意料，但这与Zisman早期的广泛研究相一致。也有些令人惊讶的是，对于与PDMS的水接触角和PDMS /水界面的界面张力，没有确定的数值被接受。对此，探讨了一些原因，并考虑了相关的局限性。PDMS表面的各种呈现方式必须对所报道的水接触角范围产生重大影响。

太阳能驱动的界面蒸发作为一种非常有前景的解决淡水短缺危机的海水淡化技术受到了广泛的关注。然而，长期太阳能海水淡化过程中的盐垢和稳定性差，严重阻碍了太阳能蒸发器的应用。此外，报告的蒸发器大多依赖昂贵的材料和复杂的制备工艺。这里，我们报道了一种简单制备聚二甲基硅氧烷/碳纳米管( PDMS / CNTs )改性三聚氰胺太阳能蒸发器的方法，用于高效蒸汽的产生和脱盐。弹性太阳能蒸发器具有( i ) PDMS相分离形成的骨架粗糙的大孔网络、高太阳吸光度( 99 % )和优异的光热性能、低热导率( 0.032   W   m-1 K-1 )和( iii )独特的润湿性(疏水上表面和亲水下部分)。因此，蒸发器的蒸发速率为1.44   kg   m-2 h-1，在1太阳光照下，去离子水的太阳能蒸发转换效率为84 %。有趣的是，蒸发器对盐水的太阳能蒸发性能与去离子水相当。此外，由于蒸发器快速补水，蒸发器在长期连续太阳能海水淡化过程中表现出优异的耐盐性和稳定性。由于蒸发器的优点和制备方法简单，蒸发器可能在太阳能海水淡化中找到实际应用。