title: Crystallization behaviour of nanostructured hybrid SiO2-TiO2 gel glasses to nanocomposites.
abstract: The crystallization behaviour of hybrid SiO2-TiO2 nanocomposites derived from titanosiloxanes by sol-gel method has been investigated depending on the type of siloxane precursor and the pirolysis temperature. The resulting hybrid titanosiloxanes, crosslinked with trimethylsilil isocyanate (nitrogen-modified) or methyltrietoxisilane (carbon-modified), were pirolyzed in an inert atmosphere in the temperature range between 600 to 1100 degrees C in order to form C-(N)-Si-O-TiO2 nanocomposites. By means of XRD, FTIR, 29Si NMR, SEM, TEM and AFM investigations have been established that the transformation of the nanostructured SiO2-TiO2 hybrid materials into nanocomposites as well as the crystalline size depend on the titanium content and the type of cross-linking agents used in the synthesizes.
authors.affiliation: Department of Silicate Technology, University of Chemical Technology and Metallurgy, 1756, Bulgaria.
authors.forename: Gerganova
authors.initials: G
authors.lastname: Tsvetelina
authors.forename: Ivanova
authors.initials: I
authors.lastname: Yordanka
authors.forename: Vueva
authors.initials: V
authors.lastname: Yuliya
authors.forename: Salvado Isabel M
authors.initials: SI
authors.lastname: Miranda
authors.forename: Fernandes Maria
authors.initials: FM
authors.lastname: Helena