Fabrication and quantitative roughness analysis of hierarchical multiscale polymer surface structures

Abstract

Nature's functional surfaces are typically hierarchical multiscale structures. There are several techniques for producing such artificial structures on polymers but their mass production is not straightforward. We present here a simple and versatile method for manufacturing hierarchical multiscale polymer surface patterns. The microroughening technique permits the single-step production of multilevel three-dimensional surface architectures in a mechanically durable nickel mold. The molding technique is suitable for area-controlled fabrication of structures with various geometrical shapes on smooth and curved surfaces. The mold structures were transferred to polypropylene surfaces by means of injection molding. The fabricated surface structures were characterized by using a filtered power spectral density method which facilitated a quantitative study of the roughness distributions at different length scales of structure periodicities. Analysis showed that the microroughening technique is an appropriate tool for controlled production of surface roughness at a micro-nanometer scale. Roughness distribution values can be used for predicting surface structure-related properties such as wetting, and the distributions can also be simulated without an experimental preparation process. The work presents a suitable approach for mass production of hierarchical polymer surfaces at different length scales and provides a new route for designing surface structures with tunable wetting properties.

Superhydrophobic Properties of Nanotextured Polypropylene Foils Fabricated by Roll-to-Roll Extrusion Coating

“…18 This R2R method is feasible for nanostructuring but is limited with regard to surface chemistry, as the relief must be formed in a UV- width of 6 in (∼150 mm). A R2R method for production of large area superhydrophobic surfaces should preferably have much higher productivity and allow structuring of common inexpensive and intrinsically hydrophobic polymers such as polyethylene, 21 cyclic olefin copolymer, 22 or polypropylene (PP) 23 to gain practical relevance. An ideal material is isotactic PP, which has good hydrophobic properties (see Table S1), has low surface energy and is inexpensive.…”

Adhesive friction and wear of micro-pillared polymers in dry contact

“…For the present study, a self-developed micro-scaled mechanical punching process was chosen and used based on its ability to quickly and accurately produce micro-pits in thin Al inlays [20][21][22][23][24][25][26][27]. These micro-pitted inlays were then used as injection moulds for producing micropillared elastomer pads.…”

Synthèse bibliographique : micro-texturation et microinjection de thermoplastiques

“…Pour ces structures, une autre approche a été utilisée regroupant des paramètres d'amplitude et de direction de structures [124,125]. La figure 14 présente la densité spectrale de puissance moyennée en fonction de la longueur d'onde déterminée à partir de mesures topographiques de surface de pièces en polypropylène et du moule correspondant [38].…”