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提出一种柔性复制法,采用微注射压缩(μ-ICM)成型具有微拓扑结构的仿生聚丙烯(PP)表面.通过复制模板上的双级微结构,所成型的PP材料表面上呈现具有锥形顶面的双级微结构,即微棱和高纵横比的微锥体.由于微锥体之间的间隙较大,水滴浸润其间隙的上方,这使该表面呈现中等黏附的超疏水特性.在μ-ICM过程中,涂覆在模板上的二氧化硅纳米粒子(SNPs)被转移到熔体中,并牢牢附着于微结构表层,赋予其表面亚微米或微米粗糙度,形成多层次微结构.在附着有亲水SNPs的微结构上,高表面自由能使水滴完全浸润微锥体之间的间隙,表面的水接触角为161.9°、滚动角大于90°,呈现极高黏附的超疏水特性(花瓣效应);在附着有疏水SNPs的微结构上,水滴受疏水SNPs的排斥而减弱与表面之间的黏附作用,表面的水接触角为163.5°、滚动角为3.5°,呈现极低黏附的超疏水特性(荷叶效应).
A flexible replication method is proposed, in which micro-injection compression (μ-ICM) is used to fabricate a bionic polypropylene (PP) surface with micro-topography.By replicating the two-stage microstructure on the template, Shaped top-level two-stage microstructures, micro-pyramids with high micro-prismatic and high aspect ratios, and because of the large gap between the micro-cones, water droplets infiltrate above the gap, giving the surface a super-hydrophobic character of medium adhesion In the μ-ICM process, the silica nanoparticles (SNPs) coated on the template are transferred into the melt and firmly attached to the surface of the microstructure, giving it a sub-micron or micro-roughness of the surface to form more Hierarchical microstructure. On microstructures with hydrophilic SNPs attached, the high surface free energy allows the water droplets to completely infiltrate the gaps between the micro-cones with a water contact angle of 161.9 ° and a roll angle of greater than 90 ° (Petal effect). On the microstructures with hydrophobic SNPs attached, water droplets were weakened by the hydrophobic SNPs and weakened their adhesion to the surface. The surface water contact angle was 163.5 ° and the rolling angle was 3.5 °. Has very low adhesion superhydrophobic properties (lotus leaf effect).