resumo
The last two decades have seen a remarkable growth in the design of new hybrid materials applied to different areas, from photonics to biomaterials, together with new coating materials with self-cleaning features. Among the various systems studied, the PDMS-SiO2 system remains as a good basis for further developments by adding other compounds such as transition metals. In this work, a detailed study of the influence of titanium or zirconium in the chemical structure and final microstructure of such hybrids was made. It was concluded that, due to the lower reactivity of the titanium alkoxide during the sol-gel preparation process, titanium is preferably located on the surface of secondary particles of silica, unlike the zirconium, which being more reactive, positions on the surface of the primary particles. This difference leads to xerogels with dissimilar characteristics and morphologies. (C) 2015 Elsevier Ltd. All rights reserved.
palavras-chave
NUCLEAR-MAGNETIC-RESONANCE; SILOXANE-OXIDE MATERIALS; SMALL-ANGLE SCATTERING; SOL-GEL CHEMISTRY; X-RAY-SCATTERING; STATE SI-29 NMR; MAS NMR; STRUCTURAL-CHARACTERIZATION; POLYSILOXANE NETWORKS; FT-IR
categoria
Polymer Science
autores
Almeida, JC; Wacha, A; Bota, A; Almasy, L; Fernandes, MHV; Margaca, FMA; Salvado, IMM
nossos autores
Isabel Margarida Miranda Salvado
Professor associado
José Carlos Martins de Almeida
Investigador Júnior
Maria Helena Figueira Vaz Fernandes
Professor(a) Jubilado(a)Grupos
G3 - Materiais Eletroquímicos, Interfaces e Revestimentos
G5 - Materiais Biomiméticos, Biológicos e Vivos
agradecimentos
This work was financed by the JECS Trust (Contract 201467), FEDER funds (Program COMPETE) and by FCT funds, by the grant SFRH/BD/72074/2010 and also developed in the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by National Funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement. The authors are grateful to Marta Ferro and Bruno Almeida, from the Electron Microscopy Service of CICECO/DEMaC, for their help with the TEM photos.