Structure formation of gypsum binder with zinc hydrosilicates

Due to high danger of mold fungi spores for humans, it is necessary to develop new fungicidal building materials, especially – materials that help to maintain biosafety in interior rooms. One of such materials is the fungicidal gypsum binder. The aim of the present work was to study the process of structure formation of gypsum in case of the presence of a previously developed fungicidal modifier which is based on hydrosilicate systems with zinc in different quantities. The studies were carried out in accordance with current regulations. The rheological and mechanical properties, including normal density, setting time and compressive strength were determined. The titrimetric method of analysis was used for determination of the content of calcium ions in the solution. It was revealed that the zinc content in the modifier does not affect the mobility of the mixture; however, it changes the rate of formation of the gypsum stone and also affects its strength. In particular, when the ratio ν(Zn)/ν(Si) is equal to 0.9, there was an increase of setting time. The mechanism of the formation of gypsum stone also changes: influence of both constructive and destructive factors simultaneously decreases. The latter was confirmed by the peculiarities of the binding of calcium ions in the presence of a fungicidal modifier.