Thermal Alternating Polymer Nanocomposite (TAPNC) Coating Designed to Prevent Aerodynamic Insect Fouling

Abstract

Insect residue adhesion to moving surfaces such as turbine blades and aircraft not only causes surface contamination problems but also increases drag on these surfaces. Insect fouling during takeoff, climb and landing can result in increased drag and fuel consumption for aircraft with laminar-flow surfaces. Hence, certain topographical and chemical features of non-wettable surfaces need to be designed properly for preventing insect residue accumulation on surfaces. In this work, we developed a superhydrophobic coating that is able to maintain negligible levels of insect residue after 100 high speed (50 m/s) insect impact events produced in a wind tunnel. The coating comprises alternating layers of a hydrophobic, perfluorinated acrylic copolymer and hydrophobic surface functional silicon dioxide nanoparticles that are infused into one another by successive thermal treatments. The design of this coating was achieved as a result of various experiments conducted in the wind tunnel by using a series of superhydrophobic surfaces made by the combination of the same polymer and nanoparticles in the form of nanocomposites with varying surface texture and self-cleaning hydrophobicity properties. Moreover, the coating demonstrated acceptable levels of wear abrasion and substrate adhesion resistance against pencil hardness, dry/wet scribed tape peel adhesion and 17.5 kPa Taber linear abraser tests.

Fabrication of Self-healing Superhydrophobic Surfaces from Water-Soluble Polymer Suspensions Free of Inorganic Particles through Polymer Thermal Reconstruction

“…The water CA with 152 • was obtained at room temperature, which was smaller than the water CAs 164 • for some polymer supehydrophobic surfaces [17]. When compared with the excellent abrasion resistance of some polymer superdhydrophbic surfaces, which could maintain its superhydrophobicity under the pressure of 17.5 KPa with 15 abrasion cycles [27] or mechanical stability after 100 abrasion cycles with sandpaper [17], the obtained superhydrophobic surfaces in the present had acceptable level of mechanical properties, which could maintain its superhydrophobicity under the pressure of 3.5 KPa with nine abrasion cycles. However, even the most durable superhydrophobic surface would eventually become damaged by the repeated mechanical abrasion or chemical etching, which would damage its low surface energy material or texture.…”

“…Polymers without solvent and inorganic matter through tribocharging [17,18] or with solvent and inorganic matter through high temperature melting for thermal reconstructions [27] have been used to fabricate robust superhydrophobic surfaces, which are highly efficient, rapid, and inexpensive. In the present study, the superhydrophobic surfaces from unitary water-soluble polymer suspensions were obtained through polymer thermal reconstruction by taking advantage of natural hierarchical microstructures just by sanding wood, instead of artificially constructing them for superhydrophobic morphology.…”

Superhydrophobic Coatings from Beeswax‐in‐Water Emulsions with Latent Heat Storage Capability

“…In fact, the morphology resembles the submicrometer vascular structure of the rose petal or similar flowers. [41] The cross-section morphology of the sample B4 (Figure 5d) also demonstrates a random, rough texturing rather than a wax particle embedded polymer matrix structure. [41] The cross-section morphology of the sample B4 (Figure 5d) also demonstrates a random, rough texturing rather than a wax particle embedded polymer matrix structure.…”

Robust Fluorine‐Free Superhydrophobic PET Fabric Using Alkaline Hydrolysis and Thermal Hydrophobic Aging Process

“…However, in order to enhance durability of nanoparticles, Bayer et al used thermal annealing to embed sprayed nanoparticles into a polymer thin film. At high T s (surrounding temperature), the polymer is melted or in a semisolid state, resulting in increased chain mobility, so that the nanoparticles on the surface of polymer can be easily infused into the polymer . Thus, the thermal annealed polymer nanocomposite showed better mechanical durability compared to the nonannealed polymer nanocomposite.…”