title: Effects of CaO/P2O5 ratio on the structure and elastic properties of SiO2-CaO-Na2O-P2O5 bioglasses.
abstract: The evolution of elastic properties and structure upon the change of CaO/P(2)O(5) ratio in SiO(2)-CaO-Na(2)O-P(2)O(5) glasses (45S5-derived and 55S4-derived) at ambient conditions has been studied by using both Brillouin and Raman spectroscopy coupled with X-ray diffraction. Under the same SiO(2)/Na(2)O ratio, it is found that a decrease in CaO/P(2)O(5) molar ratio has caused a more-polymerized silicate network via a net consumption of Q(0), Q(1), and Q(2) species yet enriching in Q(3) and Q(4) species. Brillouin experiments revealed that all the bulk, shear and Young's moduli of the glasses studied increases with the increase of CaO/P(2)O(5) molar ratio. The unexpected variation trend in shear modulus can be correlated to the contribution from cohesion, the less-polymerized phosphate Q species, and density. Compared to the 45S5-derived, the more-polymerized 55S4-deived glass has a lower bulk but slightly higher shear modulus at the given CaO/P(2)O(5) ratio.
authors: Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan, ROC. cclin@earth.sinica.edu.tw
authors: Chung-Cherng
authors: CC
authors: Lin
authors: Shih-Fan
authors: SF
authors: Chen
authors: Kak Si
authors: KS
authors: Leung
authors: Pouyan
authors: P
authors: Shen
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry*; D002412:Cations; D002516:Ceramics / Q000737:chemistry*; D003460:Crystallization; D055119:Elastic Modulus; D004548:Elasticity; D005898:Glass / Q000737:chemistry; D008422:Materials Testing; D010087:Oxides / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry; D017553:Phosphorus Compounds / Q000737:chemistry*; D033081:Shear Strength; D012822:Silicon Dioxide / Q000737:chemistry*; D017670:Sodium Compounds / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods; D013696:Temperature; D014961:X-Ray Diffraction / Q000379:methods
chemical_list: D001672:Biocompatible Materials; C022107:Bioglass; D017610:Calcium Compounds; D002412:Cations; D010087:Oxides; D017553:Phosphorus Compounds; D017670:Sodium Compounds; C096707:sodium oxide; C012500:phosphorus pentoxide; D012822:Silicon Dioxide; C016538:lime; D010100:Oxygen