Aleksandr Ketov
Perm National Research Polytechnic University, Russia
Title: Production and applications of foamed materials from synthesized silicate glasses by hydrate gasformation mechanism
Biography
Biography: Aleksandr Ketov
Abstract
Porous glasses with closed cell structure and densities lower than 250–300 kg m–3 are rather attractive as functional heat-insulating materials. It was found the possibility of obtaining low-density cellular silicate materials by the hydrate mechanism due to the stronger gas evolution in the course of the redox reaction between water vapor and carbon. The research results were obtained by synchronous thermogravimetric and MS analysis, SEM, X-ray phase analysis. It was found that raising the number of Na+ ions in the raw silicate formulation leads to an increase in the amount of bound water removed at thermal plasticity temperatures of sodium-calcium glasses (973–1073 K). The redox reactions between steam and carbon in synthesis of a cellular silicate material favor an increase in the gas evolution and a decrease in the density of the material obtained. Synthesis of glass from hydrated polysilicates in the intergrain space of dispersed glass can be used to obtain foamed-glass materials and secondary use of a low-grade sodium-calcium glass. The presented method of obtaining cellular material can use any glass wastes as a raw without extra cooking and to obtain the material similar to the commercial foamed glass of blocked and granulated types. The use of non-powder preforms enables applying efficient technological methods in production and obtaining products with new properties such as large-size items, colored ones or those acceptable for facing and also light-weight construction mixes. The applications of obtained materials are presented and discussed.