Materials based on modified gypsum for facade systems

Introduction. The use of gypsum in construction systems exposed to atmospheric influences involves the introduction of modifying additives of various types: polymer compositions, mineral fine and nanodisperse components, which can also be products of other industries. Methods and materials. To increase the weather resistance of gypsum stone, its strength characteristics and water resistance, the research considered a complex method of modifying gypsum binder by introducing aqueous solutions of polycondensation resins that harden in the material and nanocomponents. The experiment to assess the effect of the composition of complexly modified gypsum on its properties was carried out on the basis of the matrix of a complete quadratic three-factor experiment. Results. The strength of a complex modified gypsum stone during compression and bending increases by 30% and 25%, respectively, during 80 days of storage in the air. The compressive strength is 60 MPa, and the bending strength is 12 MPa. The samples can withstand 150 cycles of alternating freezing and thawing. Discussion. The introduction of polymer additives into the composition of the gypsum mixture leads to the fact that the gypsum during hydration creates a framework of crystalline aggregates of dehydrate, and the resin, when cured, forms a continuous polymer matrix. The polymer gypsum has the property of increasing the strength over time due to the ongoing polymerization of the resin. Conclusion. A weather-resistant gypsum-containing material was obtained. The use of man-made waste makes it possible to solve the problem of their disposal, which determines the reduction of the negative load on the environment. The methodology for assessing the weather resistance of gypsum stone, and, first, frost resistance, was tested.