Sun Ansu, Wang Ding, Zhou Honghao, Li Yifan, Connor Chris, Kong Jie, Sun Jining, Xu Ben Bin
Mechanical and Construction Engineering, Faculty of Engineering and Environment, Northumbria University, Newcastle upon Tyne NE1 8ST, UK.
MOE Key Laboratory of Materials Physics and Chemistry in Extraordinary Conditions, Shaanxi Key Laboratory of Macromolecular Science and Technology, School of Science, Northwestern Polytechnic University, Xi'an 710072, China.
Polymers (Basel). 2019 Jul 23;11(7):1229. doi: 10.3390/polym11071229.
Polymer surface patterning and modification at the micro/nano scale has been discovered with great impact in applications such as microfluidics and biomedical technologies. We propose a highly efficient fabricating strategy, to achieve a functional polymer surface, which has control over the surface roughness. The key development in this fabrication method is the polymer positive diffusion effect (PDE) for an ion-bombarded polymeric hybrid surface through focused ion beam (FIB) technology. The PDE is theoretically explored by introducing a positive diffusion term into the classic theory. The conductivity-induced PDE constant is discussed as functions of substrates conductivity, ion energy and flux. The theoretical results agree well with the experiential results on the conductivity-induced PDE, and thus yield good control over roughness and patterning milling depth on the fabricated surface. Moreover, we demonstrate a controllable surface wettability in hydrophobic and superhydrophobic surfaces (contact angles (CA) range from 108.3° to 150.8°) with different CA hysteresis values ranging from 31.4° to 8.3°.
聚合物在微纳尺度上的表面图案化和改性已在微流控和生物医学技术等应用中展现出巨大影响。我们提出了一种高效的制造策略，以实现对表面粗糙度具有可控性的功能性聚合物表面。这种制造方法的关键进展是通过聚焦离子束（FIB）技术对离子轰击的聚合物混合表面产生的聚合物正扩散效应（PDE）。通过将正扩散项引入经典理论对PDE进行了理论探索。讨论了电导率诱导的PDE常数与基底电导率、离子能量和通量的函数关系。理论结果与电导率诱导PDE的实验结果吻合良好，从而能够很好地控制制造表面的粗糙度和图案化铣削深度。此外，我们展示了在疏水和超疏水表面（接触角（CA）范围为108.3°至150.8°）具有可控的表面润湿性，不同的CA滞后值范围为31.4°至8.3°。
