Structure and properties of modified gypsum binder

Abstract

PurposeThe purpose of the study is regarding the development of eco-oriented technologies for obtaining the building gypsum materials with the involvement of industrial by-products or waste.Design/methodology/approachThe scanning electron microscopy, X-ray microanalysis and IR spectral analysis were used to study the structure of gypsum matrix. The method of comparison of modified and unmodified gypsum matrix was used. Physical modeling of gypsum matrix crystallization is used to study changes in the morphology of hydration products.FindingsThe experimental results show that the addition of technical soot into a gypsum binder leads to a change in the morphology of crystalline hydrates of calcium sulfate dihydrate. Results of the scanning electron microscopy, X-ray microanalysis and IR spectral analysis confirm the change of physical and mechanical characteristics of the gypsum binder due to the structural modification of the gypsum matrix with ultrafine carbon soot. The achieved degree of the structural modification of the gypsum matrix is compatible with the results obtained when the gypsum binder was modified with dispersions of carbon nanotubes.Originality/valueThe morphology of the crystalline hydrates of the gypsum matrix with the addition of 0.04%, 0.06% and 1% of the carbon soot is characterized by the transition of the classical needle-like structure of gypsum dihydrate to the lamellar structure of increased density. One can observe the formation of intergrowths around ultrafine carbon soot particles. The studied carbon additive can improve strength characteristics of the gypsum matrix.

Effective Method of Improving the Performance Properties of Wall Products On the Basis of the Gypsum Binder

“…Research conducted by various scientists over the past decades has allowed us to identify the most effective ways to increase water resistance: selection of the optimal composition of mixed binders, treatment of products based on gypsum binders with various water-repellent solutions, chemical and mineral additives, etc. [5][6][7][8] One of the methods of obtaining waterproof materials is the impregnation of products based on gypsum binders with a developed chemical solution containing calcium polysulfide and titanium dioxide. The developed method of hydrophobization of products allows their use in buildings and structures for external and internal use.…”