Liquid-Repellent Films Comprising Octamethylsilsesquioxane Selected Based on Three-Dimensional Solubility Parameters

Abstract

On the basis of Hansen solubility parameters (HSP), we investigated octamethylsilsesquioxane (OMS), a siloxane compound with a cage-like structure and methyl side chains, as an omniphobic substance. The HSP of OMS were determined through dissolution tests to be similar to those of polytetrafluoroethylene (PTFE), leading to the prediction that films comprising OMS should possess liquid-repellency comparable to films comprising PTFE. Indeed, an electroless-plated Ni–P film composite with OMS particles (Ni–P/OMS film) exhibited liquid-repellency comparable to or higher than that of the Ni–P film composite with PTFE particles, except toward 1-bromonaphthalene, which has a low surface free energy. Moreover, the hydrophilic influence of the Ni–P matrix was eliminated by the use of polydimethylsiloxane (PDMS) as the matrix instead of Ni–P, resulting in enhanced liquid-repellency and water-sliding behavior of the solution-sprayed PDMS film composite with the OMS particles (PDMS/OMS film). These films comprising OMS particles are promising candidates for nonfluorinated liquid-repellent films.

Correlations of Surface Free Energy and Solubility Parameter with Dielectric Constant and Density for Inorganic Solids

“…In addition, eq 5 was developed based on the data of liquids and has been proven to be valid for polymers. 9 Our results suggest that eq 5 is also valid for inorganic solids. Note that the γ t data of Ti 3 AlC 2 deviate obviously from the straight line, namely, its γ t-cal value (∼46.7 mJ/m 2 ) is obviously higher than its γ t-exp value (∼26.8 mJ/m 2 ), suggesting that its γ t-exp and/or δ i-exp data have large errors.…”

“…Blue square, Al 2 O 3 ; blue up triangle, ZrO 2 ; blue down triangle, SnO 2 ; blue diamond, NiO; blue left-pointing triangle, MgO; blue hexagon, Ca(OH) 2 ; green square, MoS 2 ; green circle, WS 2 ; orange square, WSe 2 ; orange circle, Sb 2 S 3 ; orange up triangle, Bi 2 Te 3 ; orange down triangle, In 2 S 3 ; orange diamond, Sb 2 Te 3 ; orange left-pointing triangle, In 2 Se 3 ; black square, BN; pink up triangle, Ti 3 AlC 2 ; red square, LDHs; purple square, Graphite. More recently, Murase and Nakamura 9 proposed an equation to correlate the interfacial free energy (γ 12 ) between two (1 and 2) substances with their δ i (δ i1 and δ i2 ) as the following:…”

Evolution of Surface Tension and Hansen Parameters of a Homologous Series of Imidazolium-Based Ionic Liquids

“…HSPs and surface energies are thus only proportional in the case of apolar organic solvents and (homo)polymers. 40,41 In contrast, for copolymer films, where segregation effects occur to minimize free energies by exposing the low-energy components to the surface, differences between surface-and bulk-HSPs were found. 41 These evaluations of polymer films show similarities to the behavior of the ILs studied in this work.…”

“…40,41 In contrast, for copolymer films, where segregation effects occur to minimize free energies by exposing the low-energy components to the surface, differences between surface-and bulk-HSPs were found. 41 These evaluations of polymer films show similarities to the behavior of the ILs studied in this work. In the case of ILs, the surface tension, which is governed by interfacial segregation effects (Figure 3), is not proportional to the HSPs estimated by the classical approach (i.e., the bulk-HSPs).…”

“…Extending previous works, 40 Murase et al provided an empirical approach to calculate the surface energies of polymer films based on HSPs of homo-and copolymer thin films. 41 Their formalism shows that surface tension, or surface energy, and HSPs are proportional to each other, but only when factoring in the segregation effects. This segregation effect can be covered via surface-HSPs, which can differ from those of bulk-HSPs determined via solubility measurements.…”