Superhydrophobic Films of Uv-Curable Fluorinated Epoxy Acrylate Resins

Photopolymerization processes are often used in industrial applications because of their solvent-free formulations and various advantages over conventional thermal processes. Fluorinated monomers and oligomers yield coatings of great interest because of the peculiar characteristics of fluorine atoms: these coatings show hydrophobicity, chemical stability, weathering resistance, etc. Novel UV-curable fluorinated epoxy acrylate oligomers were synthesized from 1 H, 1H-perfluorohexan-1-ol, 1,6- hexamethylene diisocyanate ( HDI) and epoxy acrylate (EA). The HDI plays the role of a spacer group in the side chain between the EA backbone chain and the fluorinated segment. This new spacer containing a urethane moiety with long alkyl groups can exhibit a self- organization effect through the formation of strong hydrogen bonding. This resulted in a stiffening of the whole HDI urethane-perfluoalkyl chain to form nanostructure surface segregation. The designed fluorinated EA with fluoroalkyl (C 5F11) units in the side chain exhibited a contact angle of about 151 degrees, which is in the superhydrophobic range