Sodium-free mixed alkali bioactive glasses

A1 Journal article (refereed)


Internal Authors/Editors


Publication Details

List of Authors: Delia S. Brauer, Raika Brückner, Maxi Tylkowski, Leena Hupa
Publication year: 2016
Journal: Supercapacitors
Volume number: 2
Issue number: 1
Start page: 99
End page: 110
eISSN: 2299-3932


Abstract

Two sodium-free mixed alkali series of bioactive glasses based on compositions Bioglass 45S5 and ICIE1, containing lithium and/or potassium as alkali ions, were prepared by a melt-quench route. Thermal properties showed the well-known mixed alkali effect, with glass transition and crystallisation temperatures and the coefficient of thermal expansion going either through a minimum or a maximum for the mixed alkali composition, resulting in a wider processing window. Ion release, by contrast, was controlled by the modifier ionic radius, with ion release rates in dynamic and static dissolution studies increasing for potassium-substituted glasses compared to the composition containing lithium as the only alkali ion. This was caused by pronounced changes in oxygen packing density and molar volume of the glasses owing to the differences in ionic radii (76 pm for Li+ and 138 pm for K+). Partially substituting one alkali for another therefore helps to improve high temperature processing of bioactive glasses and can also be used to control or tailor ion release.

Last updated on 2019-17-11 at 03:27