Anti-icing Coating Research Articles

Robust Prototypical Anti-icing Coatings with a Self-lubricating Liquid Water Layer between Ice and Substrate

A robust prototypical anti-icing coating with a self-lubricating liquid water layer (SLWL) is fabricated via grafting cross-linked hygroscopic polymers inside the micropores of silicon wafer surfaces. The ice adhesion on the surface with SLWL is 1 order of magnitude lower than that on the superhydrophobic surfaces and the ice formed atop of it can be blown off by an action of strong breeze. The surface with self-lubricating liquid water layer exhibits excellent capability of self-healing and abrasion resistance. The SLWL surface should also find applications in antifogging and self-cleaning by rainfall, in addition to anti-icing and antifrosting.

Design of Anti-Icing Coatings Using Supercooled Droplets As Nano-to-Microscale Probes

A multiscale simulation-based approach is presented for predicting anti-icing properties of nanocomposite coatings. Development of robust anti-icing coatings is a challenging task. An anti-icing coating that can prevent in-flight icing is of particular interest to the aircraft industry. A multiscale simulations based approach is developed to provide insights into the complex effect of coating material and surface topology on the prevention of in-flight icing. Chemical properties of different coatings and kinetics of icing or inhibition of ice nucleation are calculated from nanoscale atomistic simulations. In addition, in-flight icing environments including impingement and rolling of supercooled microdroplet and nucleation of ice under wind shear have been implemented using fluid dynamics methodologies. A model for icing in nano-to-microscale for surfaces with known chemical composition and surface topology is used for developing predictive capabilities regarding anti-icing performance of potential coatings. In this work, fluorinated polyhedral oligomericsilsesquioxanes molecules have been used to increase nanoscale roughness when embedded in a polycarbonate polymeric matrix. The findings suggest that a successful anti-icing coating will require precise control over nanoscale and microscale roughness. The multiscale methodology presented therefore can potentially help in identifying coupled effects of material, surface topology, and icing environment for promising coatings before performing icing tunnel experiments.

Characterization of titanium alkoxide sol–gel systems designed for anti-icing coatings: II. Mass loss kinetics

New coatings have been developed that display resistance to the nucleation and adhesion of ice [Simendinger, WH III, Miller, SD, Anti-icing composition. US Patent #6,702,953 2004]. These coatings contain a titanium alkoxide-based sol–gel system designed to facilitate the slow release of tripropylene glycol (TPG) and glycerol, which depress the freezing point of water. The performance and the lifetime of this coating critically depend on the rate at which TPG and glycerol are released to the coating surface. The kinetics and mechanism of this process are studied in this article. Mass loss measurements are reported for temperatures ranging from 22 to 90°C for both the isolated sol–gel and the coating. Two regions of mass loss are observed: loss of isopropyl alcohol, which begins immediately after the reactants are mixed, and loss of TPG and glycerol, which begins at a later time, extending up to several months at low temperatures. Diffusivities and activation energies for IPA and TPG/glycerol in the sol–gel are obtained from 22 to 90°C and compared to similar data obtained for an anti-icing coating containing the dispersed sol–gel. The effect of changing the sol–gel reaction conditions on mass loss kinetics is also reported.