Wetting on Patterned Adaptive Conducting Polymer Surfaces for Microfluidic Applications (PolySurf)

用于微流体应用的图案化自适应导电聚合物表面的润湿 (PolySurf)

• 批准号: 505840677
• 负责人: Professorin Dr. Sabine Ludwigs
• 金额: --
• 依托单位: Lehrstuhl für Struktur und Eigenschaften polymerer Materialien
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/505840677?language=en
• 关键词: Wetting; Patterned; Adaptive; Conducting; Polymer

The project “Wetting on Patterned Adaptive Conducting Polymer Surfaces for Microfluidic Applications (PolySurf)”, shall be implemented into current activities of the SPP 2171 on “Dynamic Wetting of Flexible, Adaptive and Switchable Surfaces”. PolySurf is based on the coupled interdisciplinary expertise of Sabine Ludwigs (polymer materials science, electrochemistry) and Holger Steeb (microfluidics, material modelling) and aims at hierarchically patterned soft surfaces which can adapt their wetting properties to externally applied electric fields. In addition to water contact angle measurements the fluid dynamics within microfluidic applications shall be explored. For adaptive surface preparation the class of conducting polymers (CPs) has been identified. CPs are gaining increasing interest for flexible actuator and sensor applications, and the interfaces of the CP polymer surfaces with liquids are extremely relevant in this context. Conducting polymers cannot only change their optical and electronic properties as function of the degree of doping, but also the wetting properties are highly influenced. In the literature extreme changes of the surface properties from superhydrophobic to superhydrophilic are reported between neutral and doped films.Within PolySurf a systematic understanding of the dynamic wetting behavior of the conducting polymer surfaces shall be established. On the materials science side both solution-processable films of poly(ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as well as electropolymerized films from branched monomers shall be prepared. Surface patterning techniques involve imprint lithography and electropolymerisation on structured electrodes and are targeted at hierarchical patterning to increase the surface roughness.Characterization of the conducting polymer surfaces will involve systematic electrochemical studies in aqueous electrolytes alongside morphological and functional property analysis by absorption spectroscopy and conductivity measurements to determine the degree of doping.In terms of wetting characterization first systematic contact angle measurements (sessile droplet, advancing/ receding contact angles) will be performed. The focus lies on water and water/ion electrolytes. Surfaces with no potential and with potential applied (during in-situ electrochemical measurements) shall be monitored in terms of their wetting behavior. As complementary method spectroscopic ellipsometry will be used alongside to identify surface variations, e.g. by swelling, when the surfaces are brought in contact with the water and the aqueous electrolytes. This shall also give information about the adaptivity of the surfaces. Beyond the study of the dynamics of three phase contact lines on surfaces, the effect on evolving wetting properties on multi-phase fluid dynamics within microfluidic applications shall be explored. Ultimately, electrochemically-switchable microfluidic devices are envisioned.

“用于微流体应用的图案化自适应导电聚合物表面润湿（PolySurf）”项目应实施到SPP 2171“柔性、自适应和可切换表面的动态润湿”的当前活动中。PolySurf基于Sabine Ludwigs（聚合物材料科学，电化学）和Holger Steeb（微流体，材料建模）的跨学科专业知识，旨在分层图案化的软表面，可以使其润湿特性适应外部施加的电场。除了水接触角测量，还应探索微流体应用中的流体动力学。对于自适应表面制备的导电聚合物（CP）的类已被确定。CP在柔性致动器和传感器应用中越来越受到关注，并且CP聚合物表面与液体的界面在这种情况下是非常相关的。导电聚合物不仅可以改变它们的光学和电子性能作为掺杂程度的函数，而且润湿性也受到高度影响。在文献中报道了中性和掺杂膜之间表面性质从超疏水到超亲水的极端变化。在PolySurf中，应建立对导电聚合物表面动态润湿行为的系统理解。在材料科学方面，应制备可溶液加工的聚（乙烯二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT：PSS）薄膜以及支化单体的电聚合薄膜。表面图案化技术涉及结构化电极上的压印光刻和电聚合，目标是分层图案化以增加表面粗糙度。导电聚合物表面的表征将涉及在水性电解质中的系统电化学研究，以及通过吸收光谱和电导率测量进行的形态和功能特性分析，以确定掺杂程度。将进行系统的接触角测量（固着液滴、前进/后退接触角）。重点在于水和水/离子电解质。应监测无电势和施加电势（在现场电化学测量期间）的表面的润湿行为。作为补充方法，将同时使用光谱椭圆偏振法来识别表面变化，例如当表面与水和含水电解质接触时通过溶胀。这还应提供有关表面自适应性的信息。除了研究表面上三相接触线的动力学之外，还应探索微流体应用中多相流体动力学对逐渐形成的润湿特性的影响。最终，设想了可电化学切换的微流体装置。