Structural coatings with dewetting and anti-icing properties, and processes for fabricating these coatings

A coating precursor for a structural coating that inhibits wetting and freezing of water, said coating precursor comprising:

• (a) a hardenable material capable of forming a substantially continuous matrix for a structural coating;
• (b) a plurality of discrete templates dispersed within said hardenable material, wherein said discrete templates have a length scale from about 50 nanometers to about 10 microns, and wherein said discrete templates are selected from polymers, inorganic salts, surface-modified derivatives thereof, or combinations thereof;
• and
• (c) a plurality of nanoparticles with an average size of about 250 nanometers or less dispersed within said hardenable material, wherein said nanoparticles consist of a different material than said discrete templates.

A process of fabricating a structural coating that inhibits wetting and freezing of water, said process comprising:

• (a) preparing a homogeneous fluid suspension comprising (i) a hardenable material;
• (ii) a plurality of discrete templates dispersed within said hardenable material, wherein said discrete templates have a length scale from about 50 nanometers to about 10 microns, and wherein said discrete templates are selected from polymers, inorganic salts, surface-modified derivatives thereof, or combinations thereof;
• and (iii) a plurality of nanoparticles with an average size of about 250 nanometers or less dispersed within said hardenable material, wherein said nanoparticles consist of a different material than said discrete templates;
• (b) applying said fluid suspension to a surface;
• (c) curing or hardening said fluid suspension to form a continuous matrix;
• and
• (d) extracting at least a portion of said discrete templates from said continuous matrix to generate a plurality of porous voids dispersed within said matrix, wherein said porous voids have a length scale from about 50 nanometers to about 10 microns, and wherein said porous voids promote surface roughness to inhibit wetting of water.

A process of fabricating a structural coating that inhibits wetting and freezing of water, said process comprising:

• (a) preparing a homogeneous fluid suspension comprising (i) a hardenable material;
• (ii) a plurality of discrete templates dispersed within said hardenable material, wherein said discrete templates have a length scale from about 50 nanometers to about 10 microns, and wherein said discrete templates are selected from polymers, inorganic salts, surface-modified derivatives thereof, or combinations thereof;
• and (iii) a plurality of nanoparticles with an average size of about 250 nanometers or less dispersed within said hardenable material, wherein said nanoparticles consist of a different material than said discrete templates;
• (b) applying said fluid suspension to a surface;
• (c) curing or hardening said fluid suspension to form a continuous matrix;
• and
• (d) extracting at least a portion of said discrete templates from said continuous matrix to generate a plurality of porous voids dispersed within said matrix, wherein said porous voids have a length scale from about 50 nanometers to about 10 microns, and wherein said porous voids promote surface roughness to inhibit wetting of water;
• wherein said structural coating comprises one or more layers, each layer including said continuous matrix, said plurality of porous voids, and said plurality of nanoparticles disposed on pore surfaces of said porous voids, to inhibit heterogeneous nucleation of water;
• and wherein said structural coating has a thickness from about 5 microns to about 500 microns.