润湿性表面液滴导向运动的研究进展

润湿性表面的液滴操控技术由于其在微流控系统设计、生物医学分析、淡水收集、喷墨打印以及换热器等领域具有广阔的应用而备受学者关注.详细介绍了液固接触和液滴运动的基本理论.综述了近年来国内外学者对于润湿性表面上液滴导向传输技术的研究进展,按不同的润湿性表面涉及的不同驱动力,归纳了液滴在润湿性梯度表面上受表面梯度驱动、在超疏水基底异性轨道表面上受重力驱动、在超疏水表面上受外场驱动的三种导向运动,着重阐述了从理论分析到实验实现润湿梯度表面驱动液滴的发展脉络、超疏水基底异性轨道表面的制备方法、液滴运输实验研究和受光、电、热、磁外场响应的不同液滴驱动传输机制,分析对比了各种液滴传输技术的优缺点.最后,提出了对润湿性表面上液滴做曲线运动过程中深入到离心力、表面张力等影响运输可控性的力学特性研究,展望了耦合多外场结合固体润湿性表面的优化设计,来控制多液滴独立导向运动的重要方向,并简要介绍了未来的应用前景.

Research Progress of Droplet Guided Motion on Wetting Surface

The droplet manipulation technology on wetting surfaces has attracted much attention because of its wide application in the fields of microfluidic system design, biomedical analysis, fresh water collection, ink-jet printing and heat exchanger. The basic theories of liquid-solid contact and droplet movement were mainly introduced. The research progress of droplet guided transport technology on wetting surfaces by scholars at home and abroad in recent years was reviewed. According to the different driving forces involved in different wetting surfaces, three kinds of droplet guided motions were summed up, which were driven by the surface gradient on the surface with wettability gradient, by the gravity on the anisotropic track surface of superhydrophobic substrate, and by the external field on the superhydrophobic surface. The development of droplet driven by wettability gradient from theoretical analysis to experiment realization, the preparation method and experimental research of superhydrophobic surface with anisotropic track were emphatically described, as well as the different transport mechanisms of droplet driven in response to light, electricity, heat and magnetic fields. The advantages and disadvantages of all kinds of droplet transport technologies were analyzed and compared. Finally, the research on the dynamic properties of centrifugal force and surface tension in the process of droplet curve motion on wetting surface was proposed. The important direction of controlling the multiple droplets for independent guided motion by combining the multiple external fields with the optimization design of solid surface was expected, and future application was briefly introduced.