title: Characterization of 50wt%SiO2-20wt%P2O5-30wt%CaO glass-ceramic powders prepared by the sol-gel process.
abstract: Glass-ceramic powders with the oxide batch formulation 50wt%SiO2, 20wt%P2O5 and 30wt%CaO were prepared by the sol-gel process using tetraethoxysilane, calcium nitrate and phosphoric acid as raw materials. The obtained gels and powders were characterized by TG-DTA thermal analysis, FTIR analyses and XRD measurements. The results indicated that (1) heating to more than 600 degrees C brought about elimination of -OC2H5 side chains from gels, and formation of a SiO2-based glass network, (2) crystallization such as Ca3(PO4)2 notably occurred in the SiO2-based glass matrix when heated to more than 900 degrees C, (3) -OH groups existed on SiO2-based glass-ceramic surfaces in the temperature region less than 900 degrees C, and (4) the melting point of this composition was more than 1400 degrees C. This study suggests that sol-gel-derived SiO2-based glass-ceramic powder containing P and Ca might be useful as bioactive implant materials.
authors.affiliation: Department of Dental Materials Science and Technology, Osaka University Faculty of Dentistry, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Taira
authors.forename: M
authors.initials: M
authors.lastname: Okazaki
authors.forename: J
authors.initials: J
authors.lastname: Takahashi
mesh_terms: D017610:Calcium Compounds / Q000032:analysis / Q000138:chemical synthesis*; D002516:Ceramics / Q000032:analysis / Q000138:chemical synthesis*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003764:Dental Materials / Q000032:analysis / Q000138:chemical synthesis*; D004055:Differential Thermal Analysis; D005782:Gels; D005898:Glass / Q000032:analysis / Q000737:chemistry*; D010087:Oxides / Q000032:analysis / Q000138:chemical synthesis*; D010316:Particle Size; D017553:Phosphorus Compounds / Q000032:analysis / Q000138:chemical synthesis*; D011208:Powders; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D017610:Calcium Compounds; D003764:Dental Materials; D005782:Gels; D010087:Oxides; D017553:Phosphorus Compounds; D011208:Powders; C012500:phosphorus pentoxide; D012822:Silicon Dioxide; C016538:lime