RESEARCH OF PROCESSES OF FORMATION OF STRUCTURE OF COMPOSITE THERMAL INSULATION MATERIALS ON THE BASIS OF LIQUID GLASS BTAINED WITH THE USE OF ENVIRONMENTALLY SAFE MICROWAVE TECHNOLOGIES

Abstract

Improving the efficiency of energy use is one of the main tasks in the chemical industry not only in Ukraine but also around the world, which is due to the steady rise in energy prices. In this regard, an effective way to save energy is the thermal modernization of buildings, industrial equipment and communications with thermal insulation materials. It should be noted that the share of domestic materials in the Ukrainian market is not more than 30 %. Therefore, the creation of new types of insulation materials is a very important task. This material is a heat–insulating material based on liquid glass, created with the involvement of microwave radiation as an alternative to traditional convective thermal heating. The technology of production of heat–insulating materials on the basis of liquid glass by hot foaming involves obtaining the material in the form of granules, not plates, due to the difficulty of uniform heating of the inner layers of large samples. The problem of large–scale production of high–quality thermal insulation materials based on liquid glass in plate form is not solved due to poor heating of the inner layers of the plate due to the low thermal conductivity of the swollen outer layers. That is why the production of composite thermal insulation materials based on granular filler and liquid glass binder is proposed to be carried out under the action of microwave radiation. Thermal insulation properties of expanded materials are directly determined by their macrostructure. Therefore, the purpose of this study is to determine changes in the structure of the material from the type and amount of ingredients used in the liquid glass composition. On the basis of the conducted researches it is shown that the materials with use as a filler of zinc oxide and as a gas–forming agent of hydrogen peroxide have the most ordered structure. It is established that their use in the amount of 9–10 wt.h. provides a rate of gas evolution and growth of pore centers, which is comparable to the process of curing composition, which allows to obtain materials with a homogeneous, fine and closed–porous structure, which provides high insulating properties with a thermal conductivity coefficient of 0.05–0.055 W / m · K, which meets the requirements for thermal insulation materials.