Formation of Nanostructure during Replication of a Hierarchical Plant Surface

Abstract

Plant and animal surfaces have become a model for preparing special synthetic surfaces with low wettability, reflectivity, or antibacterial properties. Processes that lead to the creation of replicas of natural character use two-step imprinting methods. This article describes a technique of synthetic polymer surface preparation by the process of two-stage imprinting. The laboratory-prepared structure copies the original natural pattern at the micrometer and sub-micrometer levels, supplemented by a new substructure. The new substructure identified by the scanning electron microscope is created at the nanometer level during the technological process. The nanostructure is formed only under the conditions that a hierarchical structure forms the surface of the natural replicated pattern, the replication mold is from a soft elastomeric material, and the material for producing the synthetic surface is a polymer capable of crystallizing. A new nanometer substructure formation occurs when the polymer cools to standard laboratory temperature and atmospheric pressure.

Creation of an Aluminum Alloy Template with a Surface Structure by Micro-Milling for Subsequent Replication of the Microstructure to Achieve Hydrophobicity

“…Using the CAD model and the chosen parallel machining strategy, tool paths, traverse distances, safety distances, tool passes, and cutting conditions were precisely defined. For the subsequent replication of the specimens, the negative of the selected relief was first created and machined to produce a positive microstructure using the replication process [5,9,10]. The dimensions of the relief were adjusted to suit the needs of the micro-milling technology, depending on the geometry of the selected cutting tool.…”

“…However, for this experiment, this is not a negative effect. On the contrary, grooves, valleys, and burrs can, in some cases, have a positive effect on the resulting surface structure due to the increase in the specific surface area of the polymer surface and consequently increase the hydrophobicity of the structure [5,9,10]. On the upper edge of the profile, burrs can be observed instead of a rounded edge with the size of the rounding according to the radius of the cutting edge.…”

“…The resulting dimensional accuracy (p p , h p ) and surface quality (S a , size and occurrence of burrs, etc.) significantly influence the further development of the fabrication of the final replica of a given structure [5,9,10], especially when semi-crystalline polymer materials are used.…”

“…On the surface of plants, there are wax-based structures, which are often also silica-based. The surfaces of animal objects are largely equipped with protein-based structures-hairs, scrubs, scales, and others [1][2][3]5].…”