SiO2/PDMS functionalized hybrid ceramics: effect of functional group on hydrophobic behavior

Abstract

In this paper, the hydrophobic effect of the functional group in a hybrid ceramic synthesized from tetraethyl orthosilicate (TEOS) and polydimethylsiloxane (PDMS) is investigated. The hybrid ceramics were synthesized using di-butyl-di-di-tin laurate (DBTL) as a polycondensation catalyst and different concentrations of the polysiloxane chain varying from 20-40%w. Infrared spectroscopy confirmed the formation of the hybrid material, observing the corresponding signals for the siloxane bond (Si–O–Si) corresponding to the silica network, inorganic fragment (1100 cm–1 ) and those corresponding to the polymer chain (785 cm–1 ) besides, the Si–C bond of the polymer is presented at 1250 cm–1 . The amino functional group was identified as a low intensity signal at 1300 cm–1 (N–C) and 1204 cm–1 (Si– N); on the other hand, the phenyl group was present at 3080 cm–1 for the C–H group of the aromatic ring and with the C=C bond of the ring at 1429, 794 and 845 cm–1 . While the hydrophobic character was evaluated with the contact angle  obtaining a hydrophobic to superhydrophobic behavior with  de 110-130º.