Impact of the TiO2 nanoparticles on the properties of urethane-siloxane copolymers

Rutile/anatase TiO2 was incorporated in different amounts (1, 2, 3 and 5 wt.%) in relative to the polyurethane-siloxane (PUS) matrix in order to investigate the influence of nano-fillers on the hydrophobicity, thermal properties and morphology of the PUS. A series of PUS nanocomposites (PUSN) based on α,ω-dixydroxy-ethoxypropyl-poly(dimethylsiloxane) (EO-PDMS) as the soft segment (SS) and 4,4'-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (BD) as the hard segment (HS), was prepared via two-step polyaddition reaction in solvent mixture. Prepared PUSNs were characterized using FTIR spectroscopy, thermogravimetric analysis, water absorption, water contact angle and AFM analysis. In summary, the synthesized PUSNs and especially PUSN with 2 wt.% of TiO2 had better water resistivity and nonwettability, higher thermal stability, and more pronounced surface morphology that can be potentially used as protective coatings