Micro injection molding is in great demand due to its efficiency and applicability for industry. Polymer surfaces having micro-nanostructures can be produced using injection molding. However, it is not as straightforward as scaling-up of conventional injection molding. The paper is organized based on three main technical areas: mold inserts, processing parameters, and demolding. An accurate set of processing parameters is required to achieve precise micro injection molding. This review provides a comparative description of the influence of processing parameters on the quality of final parts and the precision of final product dimensions in both thermoplastic polymers and rubber materials. It also highlights the key parameters to attain a high quality micro-nanostructured polymer and addresses the contradictory effects of these parameters on the final result. Moreover, since the produced part should be properly demolded to possess a high quality textured polymer, various demolding techniques are assessed in this review as well.

We describe a simple method for fabricating superhydrophobic high temperature vulcanized (HTV) silicone rubber surfaces by direct replication using a compression molding system. The resulting rubber samples possessed micro-nanostructures on the surface. This micro-and nanoscale roughness produced a water contact angle of >160º and a contact angle hysteresis of <3º. The roughness patterns on chemically etched aluminum surfaces, which served as templates, were successfully replicated on the rubber surfaces. An antistiction coating applied to the template surface ensured that the rubber was completely removed during demolding and that the replicated micro-nanostructures on the silicone surface were preserved. Surface roughness of the aluminum templates was optimized at HCl concentrations of 15 wt.%, with a lower roughness value observed at acid concentrations above and below this value. The developed HTV silicone rubber surfaces also demonstrated a freezing delay and a self-cleaning capacity.

Superhydrophobic materials are found in a suite of scientific and industrial applications, and given their broad potential use, there is great interest in facilitating their mass production. Although numerous methods have been used to produce superhydrophobic materials, only a few are capable of fabricating superhydrophobic surfaces and materials at an industrial scale. Techniques such as injection molding, compression molding, hot embossing, and polymer casting play an important role in the mass production of superhydrophobic polymer surfaces. This technical literature review summarizes recent advances in the polymer molding processes used to fabricate superhydrophobic materials. Here, we review replication methods and the materials that can be used by these approaches. We also evaluate the advantages and disadvantages of these methods and discuss the challenges of molding and demolding single-level structures (e.g., microstructures and nanostructures) and multilevel structures (e.g., micro-nanostructures, micromicrostructures, and micromicro-nanostructures), with a focus on superhydrophobic surfaces. We evaluate the relationship between structure geometry and the wettability of a surface, highlighting the effect of structure type and size in achieving the desired wettability. We then offer perspectives, discuss current limitations, and suggest required studies. This review aims to assist researchers in understanding the fundamentals related to the fabrication of patterned surfaces via polymer molding processes and offer avenues for the successful creation of superhydrophobic polymeric surfaces.

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Epoxy composites were prepared with different contents of hydrophobic silica aerogel particles to investigate their mechanical, thermal, and hydrophobic properties. The composites, particularly the one containing 1 wt % silica aerogel, showed remarkable toughness and yielding behaviors compared to neat epoxy, with its brittle behavior. As the content of silica aerogel increased, the thermal properties of the composites (e.g., thermal conductivity and thermal stability) improved. This was due to the very low thermal conductivity and high thermal stability of the silica aerogel particles. Moreover, the use of the hydrophobic silica aerogel led to the development of composites with hydrophobic properties. To examine the hydrophobicity more deeply, a series of water‐uptake tests were performed, and the results show that the composite with 3 wt % silica aerogel absorbed 50% less water than the neat epoxy. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45706.