"Borate glasses have recently been developed for a variety of medical applications, but much less is known about their structures and properties than more common silicate glasses. Melt properties and crystallization tendency for compositions in the Na2O-CaO-B2O3 system were characterized using differential thermal analysis and viscosity measurements. Characteristic viscosity (isokom) temperatures varied with the ratio between the modifier content (Na2O+CaO) and B2O3, particularly at lower temperatures, consistent with the changes in the relative concentrations of tetrahedral borons in the glass structure.
Similar glasses were used to study dissolution processes in water. These alkali-alkaline earth glasses dissolve congruently and follow linear dissolution kinetics. The dissolution rates were dependent on the glass structure, with slower rates associated with greater fractions of four-coordinated boron. For glasses with a fixed alkaline earth identity, the dissolution rates increased in the order Li
Finally, a seven component (Na2O, MgO, CaO, B2O3, SiO2, and P2O5) mixture model design was used to predict composition-property relationships to optimize the properties of new borate-based bioactive compositions for specific applications. Melt viscosity, thermal expansion coefficient, liquidus temperature and crystallization tendency were determined, as were dissolution rates in simulated body fluid (SBF)"--Abstract, page iv.
Brow, Richard K.
Day, D. E.
Ray, C. S.
Smith, Jeffrey D.
Samaranayake, V. A.
Materials Science and Engineering
Ph. D. in Materials Science and Engineering
Missouri University of Science and Technology
Journal article titles appearing in thesis/dissertation
- Viscosity, crystallization and glass forming tendency of Na2O-CaO-B2O3 melts
- Spectroscopic study of the structure of ternary alkali-alkaline earth-borate glasses
- Dissolution behavior of ternary alkali-alkaline earth-borate glasses
- Compositional design of borate-based bioactive glasses
xiv, 165 pages
© 2014 Kathryn Lynn Goetschius, All rights reserved.
Dissertation - Open Access
Glass -- Research
Electronic OCLC #
Goetschius, Kathryn Lynn, "The effect of composition on the viscosity, crystallization and dissolution of simple borate glasses and compositional design of borate based bioactive glasses" (2014). Doctoral Dissertations. 2341.