Patternable Poly(chloro-p-xylylene) Film with Tunable Surface Wettability Prepared by Temperature and Humidity Treatment on a Polydimethylsiloxane/Silica Coating

Abstract

Poly(chloro-p-xylylene) (PPXC) film has a water contact angle (WCA) of only about 84°. It is necessary to improve its hydrophobicity to prevent liquid water droplets from corroding or electrically shorting metallic circuits of semiconductor devices, sensors, microelectronics, and so on. Herein, we reported a facile approach to improve its surface hydrophobicity by varying surface pattern structures under different temperature and relative humidity (RH) conditions on a thermal curable polydimethylsiloxane (PDMS) and hydrophobic silica (SiO2) nanoparticle coating. Three distinct large-scale surface patterns were obtained mainly depending on the contents of SiO2 nanoparticles. The regularity of patterns was mainly controlled by the temperature and RH conditions. By changing the pattern structures, the surface wettability of PPXC film could be improved and its WCA was increased from 84° to 168°, displaying a superhydrophobic state. Meanwhile, it could be observed that water droplets on PPXC film with superhydrophobicity were transited from a “Wenzel” state to a “Cassie” state. The PPXC film with different surface patterns of 200 μm × 200 μm and the improved surface hydrophobicity showed wide application potentials in self-cleaning, electronic engineering, micro-contact printing, cell biology, and tissue engineering.

Variability in the Wettability and Water Storage Capacity of Common Oak Leaves (Quercus robur L.)

“…In the light of physical knowledge of the processes of wetting and retaining water on the surface of various bodies, and not just the plant material [5,6], it should be assumed that the wetting and entrainment of water on plant surfaces (and other terrestrial surfaces) during storms is influenced by leaf surface traits [7][8][9][10][11] and rainfall characteristics [12]. Field studies have estimated that the crowns of deciduous and coniferous trees are saturated by 0.5-8.2 mm of rainfall [2,13,14].…”

A versatile “3M” methodology to obtain superhydrophobic PDMS-based materials for antifouling applications

“…Second, the methods to achieve superhydrophobicity with PDMS with nanoparticles are based on one-step coating strategies ( Steele et al, 2009 ), which are easier and less costly than strategies such as replicating, laser engraving, and electrospinning. Third, hierarchical roughness can be obtained via the spontaneous formation of nanoparticle aggregates ( He et al, 2011 ; Gao and Yan, 2012 ; He et al, 2012 ; He et al, 2013 ; Yu et al, 2018 ). Here, we will use materials based on PDMS with nanoparticles to exemplify the “3M” methodology in the following sections.…”

Femtosecond laser-scribed superhydrophilic/superhydrophobic self-splitting patterns for one droplet multi-detection

“…The unique wetting phenomenon exhibited by superwettable patterned composite surfaces has enabled a wide variety of applications, such as microelectrode patterning, 18–20 water collection, 21–23 biological monitoring 24 and analyte enrichment, 25,26 and thus also holds great potential for microfluidic applications. 27–32…”

“…The unique wetting phenomenon exhibited by superwettable patterned composite surfaces has enabled a wide variety of applications, such as microelectrode patterning, [18][19][20] water collection, [21][22][23] biological monitoring 24 and analyte enrichment, 25,26 and thus also holds great potential for microfluidic applications. [27][28][29][30][31][32] Recently, the development of micro/nanotechnology has enabled the design and manufacture of high-precision surfaces with composite patterns. Various methods have been developed and successfully applied for precise droplet manipulation.…”