(334bh) Superhydrophobic Coatings Synthesized By High-Temperature Free-Radical Polymerization

Superhydrophobic coatings have many applications. Examples include self-cleaning and anti-ice surfaces, anti-fouling marine coatings, and anti-bacterial coatings for medical devices. To develop a superhydrophobic coating, low surface energy and high surface roughness in micro/nano scale are required. Fluoropolymers can decrease the surface energy of a coating significantly by orienting themselves in the coating-air interface. To induce surface roughness, different strategies including solvent evaporation, non-solvent induced phase separation, vapor induced phase separation, solvent/co-solvent induced phase separation, and polymerization-induced phase separation are applied. Incorporating nanoparticles into coatings is another strategy for increasing the surface roughness of coatings. Higher roughness means higher pockets of air between a liquid droplet and a solid surface, leading to a higher contact angle.

Silica is a nanoparticle widely used in high-performance coatings. Silica in a coating provides the coating with high thermal resistance, improved mechanical properties, resistance to corrosive solvents and so on. In case of covalent bonding between the silica surface and the polymeric matrix, these improvements in properties are much more significant .

Acrylate monomers with a long alkyl chain are highly hydrophobic and undergo free-radical polymerization. Such polyacrylates have already been used for the fabrication of implants thanks to their high anti-bacterial activity and biocompatibility. In this paper, we present results from in-situ polymerization of a mixture of silica and a hydrophobic acrylate monomer. Different grades of silica with different surface chemistry were used for the polymerization. After the polymerization, the nanocomposites were coated on glass substrates via spin coating. The water contact angles of the coatings were measured by the goniometry technique. Other characterization techniques including TGA, EDS, and SEM are also applied to fully characterize the products.

Research Interests:

• Polymerization science
• Polymer nanocomposites
• Mathematical modeling of polymerization reactors
• Polymer coatings and thin films
• MXene synthesis and surface modification
• Polymer melt processing