Filmogen organic-inorganic hybrids obtained by sol-gel in the presence of cationic polymer

Self-standing and coated-on-glass films were prepared from polymer-inorganic ormosils, using the cationic polymer poly(methacrylamide propyl quaternarydimethyldodecyl bromide). The inorganic compound was grown in sol-gel reactions based on methyltriethoxysilane (MeTES), with or without addition of the titanium-precursor: tetraisopropyl orthotitanate. As evidenced by thermogravimetric analysis and differential scanning calorimetry data, the thermal properties of the films are highly dependent on the internal morphology. Inorganic granules with a TiO2 rich shell have a more polar surface, which stimulates stronger electrostatic interactions with the polymer, hence, a reduced mobility for the amino end and a smaller probability to have amino ends engaged in interactions at the surface of the granules. Coated-on-glass films drawn from pure cationic polymer suffer from partial dewetting. Topographic and force-versus-distance recordings using atomic force microscopy showed a change in the energy balance and no dewetting regions were encountered for polymer/MeTES based composites. However, because of nongrafted polymer, these films are not immune at washing with water/ acetone. Explorations of antibacterial activity against the gram-negative bacteria, Pseudomonas aeruginosa, were done using ormosil films with alkoxysilanes combinations.