Font Size: a A A

Study On Fabrication And Performance Of Bionic Nanostructure On Polymer Surface

Posted on:2011-10-21Degree:MasterType:Thesis
Country:ChinaCandidate:J BianFull Text:PDF
GTID:2121360305484309Subject:Materials Processing Engineering
Abstract/Summary:PDF Full Text Request
In this thesis, the polymer surfaces with micro-and nano-structures were prepared in order to enhance the polymer surface hydrophobicity. The thesis work includes two parts:In the first part, the micro-and nano- wave-like parallel grooves on poly(dimethyl siloxane) (PDMS) surface were fabricated by three methods, namely, the shrinking during chemical crosslinking under heat, lateral stress shrinking, and uniaxial stress shrinking, based on the principle of stress releasing. Afterwards, the large AR grooves and nest grooves on PDMS surfaces were built by replicating and successive plasma oxidation. The results showed that, mechanically-induced surface cracks created stress discontinuities that converted the global biaxial stress state to local uniaxial stresses, and thus produced aligned wrinkles across the PDMS surface addition; the low strain energy release rate was good for regulating surface grooves. The large AR grooves and nest grooves can further enhance the PDMS surface hydrophobicity.In the second part, we made bionic nano arrays on three polymers by using templet replication. The oxidation of aluminum sheet to produce nano-sized holes, and the replication processing technique to prepare nano-array structures on the surface of three polymers, namely, polystyrene, poly(methyl methacrylate) and polycarbonate, as well as the hydrophobicity of the polymes were investigated. The results showed that, closely-packed nano-sized bowls structure was obained by stripping the oxidation layer on the sheet after a long time oxidation in oxalic acid solution, and nano-hole and inclined nano-holes on Al surface was fabricated by oxidation in oxalic acid solution and further erosion in phosphate acid solution from closely-packed nano-sized bowls structure. With the structures on Al sheets as templets, polystyrene with nano-hills, nano-pillars and nano-cones structures were obtained. It was also found that, perfect nano-structures on PS surface were obtained by free radical polymerization of styrene monomer; flowability of polymer solution and heat pressing temperature dominated replication quality. we find that PS nano-hill arrays, nano-pillar arrays and nano-cone arrays largely enhanced the polystyrene surface hydrophobicity as compared to the smooth PS surface, and the efficacy of polystyrene surface hydrophobicity was in the order: nano hills< nano pillars< nano cones. Among them, nano-cone structures contributed the super-hydrophobicity of polystyrene surface.
Keywords/Search Tags:Poly(dimethyl siloxane), polystyrene, Micro-and nano-structures, Anodic alumina template, super-hydrophobic surfaces
PDF Full Text Request
Related items