Preparation and in vitro evaluation of porous silica gels.
Porous silica gels with high surface areas were prepared from tetraethylothosilicate and polyacrylic acid (PAA) of high molecular weight in acidic media by a sol-gel method. PAA content and ageing temperatures were varied in order to obtain different microstructures. Samples were sintered at temperatures up to 400 degrees C, and subjected to in vitro evaluation by soaking them in acellular inorganic solutions at 37 degrees C and pH 7.3. Surface precipitation of carbonate-apatite on some of the gels was observed by FTIR spectroscopy, scanning electron microscopy and EPMA. Silica dissolution and re-precipitation phenomena were also observed. The relationship between both phenomena during the in vitro test is discussed mainly in terms of structural and microstructural features of the gel.
Gallardo
Janet
J
Department of Ceramics, Instituto de Investigaciones en Ciencia y Tecnología de Materiales (INTEMA) UNMdP-CONICET, Av. Juan B. Justo 4302, CP 7600, Mar del Plata, Argentina.
Galliano
Pablo G
PG
Porto López
J M
JM
D000180:Acrylic Resins / Q000737:chemistry*; D001031:Apatites / Q000737:chemistry; D001826:Body Fluids / Q000737:chemistry; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016062:Porosity; D012821:Silanes / Q000737:chemistry*; D058428:Silica Gel; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D013696:Temperature
D000180:Acrylic Resins; D001031:Apatites; D012821:Silanes; C040733:tetraethoxysilane; C006903:carbopol 940; D058428:Silica Gel; D012822:Silicon Dioxide