One of the most important components of refractory glass-fiber heat insulation products which determine the main working properties is the binder, which links the separate glass fibers and gives the strength of the finished articles.Moreover, the binder has a significant effect on the density and thermal conductivity of the heat-insulation products and also on their shrinkage during service.In addition, the effect of the type of binder on the properties of thermal-insulation glass-fiber refractory articles has received inadequate coverage in the literature.Thus, in [i] it was shown that the nature of the binder has a significant effect on the adsorption capacity of the fiber, on its structural features at high service temperatures, and also on the temperature interval in which a change occurs in the mass and volume of the materials. According to the data in [2], inorganic binders do not affect the crystallization of the refractory glass fiber, which is barely possible, particularly at high temperatures when an interaction is observed in most cases between the glass fiber and the binder.The present paper gives some results from a study of the effect of the binder on the main properties of glass-fiber refractory products.We used water glass, silica sol, chromium--aluminophosphate binder (CAPB), and an alumina binder of the bentonite type as the inorganic binders for the production of articles based on aluminosilicate fibers; for the organic binders we used a polyvinyl acetate dispersion (PVAD)We used the refractory glass-fiber ~ and 46-48% Si02 developed for the first of an aluminosilicate composition with 51-53% AI=Os time in the USSR at the All-Union Scientific-Research Institute of Glass Laminates and Fibers and produced at the Bogdanovich Refractory Plant [3][4][5].Because of the different natures of the binders and, consequently, of their adhesive quality, experimental amounts of binder were different and varied from 4-16 to 50-65% (dry material).The main criterion was the use of a minimum amount of binder that would ensure the ultimate bend strength of ~ 0.5 MPa after drying at least.All the specimens with the various binders were made up as a slurry and subsequently evacuated and pressed in equipment which included a mill and vacuum press. The specimens were dried in a hot chamber at 120-150~ for 16-18 h and then fired at various temperatures between 400 and 1300~ with a dwell of 2 h at each temperature.We then studied the temperature dependence of the main properties of the articles and the interaction process between the binder and the glass fiber.The linear shrinkage (or growth) of the heat-insulation products was calculated by measuring the linear dimensions of the specimens to an accuracy of 0.I mm; the ultimate bend strength was determined on an MR-0.5-1 device using a three-point bend method; the specimen was loaded at the center and the distance between the supports was 40 mm. The thermal conductivity of the specimens was determined in a device specially developed at the Ukrainian Institute of Refra...
