Design and preparation of sandwich-like polydimethylsiloxane (PDMS) sponges with super-low ice adhesion

Abstract

The mitigation of ice on exposed surfaces is of great importance to many aspects of life. Ice accretion, however, is unavoidable as time elapses and temperature lowers sufficiently. One practical solution is to reduce the ice adhesion strength on a surface to as low as possible, by either decreasing the substrate elastic modulus, lowering surface energy or increasing the length of cracks at the ice-solid interface. Herein, we present a facile preparation of polydimethylsiloxane (PDMS) based sandwich-like sponges with super-low ice adhesion. The weight ratio of the PDMS prepolymer to the curing agent is tuned to a lower surface energy and elastic modulus. The introduction of PDMS sponge structures combined the advantages of both a reduced apparent elastic modulus and most importantly, the macroscopic crack initiators at the ice-solid interface, resulting in dramatic reduction of the ice adhesion strength. Our design of sandwich-like sponges achieved a low ice adhesion strength as low as 0.9 kPa for pure PDMS materials without any additives. The super-low ice adhesion strength remains constant after 25 icing and deicing cycles. We thus provide a new and low-cost approach to realize durable super-low ice adhesion surfaces.

Nanoscale Correlations of Ice Adhesion Strength and Water Contact Angle

“…Such an experimental disagreement might stem from material or substrate deformations during detachment, an incomplete ice-solid contact [36], the so-called nanoscale crack initiators [6] or the difference in other surface parameters for the real surfaces during experiments compared to the ideal surface investigated in this study. Several surface parameters which are known to impact the ice adhesion strength, such as material softness and elastic modulus [14], have not been included in this study. Furthermore, real materials are often deformed upon detachment, and work may be done in forming micro-cracks within the ice.…”

“…Surfaces with ice adhesion strength below 10 kPa are often denoted as super-low, or ultra-low, ice adhesion surfaces (SLIAS) [6]. In the past years, examples of surfaces reaching below 1 kPa have also been reported [12][13][14]. However, the field of low ice adhesion materials research has been known to operate by continuum theory or a trial-and-error strategy, where the focus has been on developing new surfaces and coatings without fully understanding the underlying mechanisms [15][16][17].…”

Interlaboratory Study of Ice Adhesion Using Different Techniques

“…The VST is very common due to its simple and economical set-up and performance, although the location of the force probe impacts the ice adhesion strength greatly [32], and the stress distribution may not be completely uniform [8,17,18]. The VST is commonly in use by several research groups [7,11,[32][33][34][35][36][37][38][39], and has been attempted as a standard for ice adhesion measurement utilizing only commercially available instruments [14]. When comparing reported ice adhesion strengths, it is also necessary to include the type of ice tested.…”

Epidermal Gland Inspired Self-Repairing Slippery Lubricant-Infused Porous Coatings with Durable Low Ice Adhesion

“…A measure of 5 µL of deionized water was dropped on the surfaces of the samples and the water contact angle was recorded as a function of time. The ice adhesion strength was measured by a universal mechanical tester (Instron Model 5944) equipped with a homemade cooling chamber, as described in previous reports [16,19]. A polypropylene tube with a 1 mm thick wall and 15.3 mm inner diameter was placed onto the coatings acting as an ice mold, and then 5 mL deionized water was syringed into the tube.…”

“…So far, intensive studies on passive icephobic materials have led to the discovery of various strategies, including superhydrophobic surfaces and lubricant-infused surfaces [7,[16][17][18][19][20][21]. Although the superhydrophobic surfaces have been successfully utilized for delaying water droplet freezing time and/or reducing water droplet contact area [20,[22][23][24][25], they display mechanical weakness and/or the interlocking effect in harsh humidity, owing to hierarchical surface structures [26,27].…”