单分散聚苯乙烯微球的表面皱纹化  

Surface Wrinkling on Monodispersed Polystyrene Microspheres

作　　者：杨秀[1] 尹健[1] 韩雪[1] 鲁从华[1] 

机构地区：[1]天津大学材料科学与工程学院,天津300072

出　　处：《高分子学报》2016年第3期337-344,共8页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21074090;21374076)资助项目

摘　　要：首先制备了不同粒径的未交联的单分散聚苯乙烯(PS)微球;而后通过离子溅射技术在PS微球表面沉积了一层均匀光滑的铂(Pt)壳层,得到了PS-Pt核壳结构的复合微球;最后借用溶剂溶胀法诱导微球表面起皱的发生,从而制备了表面带有皱纹微结构形貌的PS微球.系统考察了微球表面Pt层厚度(t)、微球粒径(D)、溶剂组成(即溶胀度)等因素对球面起皱和皱纹形貌的影响,获得了球面皱纹周期与Pt层厚度的指数关系;结合理论分析了其起皱行为,实验结果与理论分析相吻合.此外,将表面起皱与表面等离子体刻蚀技术相结合,实现了表面带有纳米点状凸起与皱纹复合微结构形貌的PS微球的可控制备.Firstly,monodisperse polystyrene（ PS） microspheres with different diameters are prepared.Subsequently,a uniform and smooth Pt film is formed on the PS microsphere surface by ion sputtering,yielding the corresponding PS-Pt core-shell composite microsphere. Finally,surface wrinkling on these PS composite microspheres is induced by solvent swelling. Consequently,PS microspheres with various surface wrinkle patterns are obtained. Hereinto,the effects of experimental parameters（ e. g.,Pt film thickness,microsphere diameter and the swelling solvent） on the surface wrinkling behaviors have been investigated systematically.The results reveal that whether the surface wrinkling on the composite microspheres takes place or not,the resulting wrinkling morphologies are determined by the overstress σ^R/ σ^Rc. Here the overstress can be tuned by the Pt film thickness,microsphere diameter and the swelling degree. It is noted that a power-law dependence of the wrinkling wavelength on Pt film thickness is obtained and the experimental results are in agreement with the results of the theoretical simulation and calculation. Additionally,combining surface wrinkling and surface plasma etching technique,PS microspheres with composite morphologies of nano-protrusion and wrinkles have been prepared by exposure of PS microspheres to oxygen plasma before ion sputtering of the Pt film. It is envisioned that the introduced strategy in principle could be applied to other curved surfaces for expeditious generation of well-defined wrinkle morphologies,which enables not only the fabrication of solids with multifunctional surface properties,but also provides important implications for the morphogenesis in soft materials and tissues.

关 键 词：聚苯乙烯 复合结构微球 球面起皱 

分 类 号：O632.13[理学—高分子化学]