Design of robust superhydrophobic coatings using a novel fluorinated polysiloxane with UV/moisture dual cure system.

A novel robust and flexible superhydrophobic fluoropropyl methylsiloxane-dimethylsiloxane multi-block copolymer containing methacryloxyl group was synthesized via ring-opening polymerization, followed by macromolecular modification using 3-(trimethoxsilyl) propyl methacrylate (TMPMA). The propionyloxy group of MAc(PTFMS- alt -PDMS) could be crosslinked under UV irradiation, and its silicon methoxy group (-SiOCH 3) was simultaneously condensed under moisture ambient, so as to acquire both higher crosslink density and adhesion strength duo to the dual-curing mode. After coating and curing MAc(PTFMS- alt -PDMS) on the surface of cotton fabric, a robust superhydrophobic elastomer coating was obtained. The elastomer exhibited excellent mechanical properties with a tensile strength >4.0 Mpa and an elongation at break >300%. Moreover, the elastomer exhibited superhydrophobic properties (contact angle CA > 150o) and good adhesion properties (shear strength >3.7 Mpa) on various inorganic and organic substrates such as steel, glass, paper, and polyethylene (PE) films, with the assistant of the hydrophobic silica particles. The excellent flexibility and adhesive strength of the MAc(PTFMS- alt -PDMS) allowed a PE film to be bent at a large angle (120o). The results obtained here demonstrate that this material has good application prospects where flexible superhydrophobic coatings are desired. [ABSTRACT FROM AUTHOR]