Title : The influence of the nature of aqueous solutions on the surface structure and properties of gypsum stone
Abstract:
The results of the work prove that the type of solution is an influential factor for the mechanical and even visual properties of gypsum stone. Thus, the use of soapy and especially acidic water gives very porous samples - due to the formation of bubbles. Water-soluted protein gives a heterogeneous structure of the stone. Fatty water (with corn oil) and especially acrylic emulsions make gypsum stone more solid. Only acrylic emulsions and soapy-water strengthens hardened gypsum. Acidic water forms strong gypsum material, however, the presence of pores reduces the strength parameters. The strength of gypsum stone increases in series protein<soapy<acidic*<pure<acrylic primer<acrylic <acrylic varnish.
After hard heating of the samples at 200 ° C, most of the samples lose their original strength. But gypsum with fatty water is significantly strengthened, which can be explained by the self-polymerization of oil inclusions in gypsum upon heating, with the formation of a polymer reinforcing framework. Thus, it is shown that the type of aqueous solution greatly affects the structural surface, appearance, hardening time, and mechanical properties of gypsum stone.
