Influence of the composition of cement systems on the activity of modifying additives

Abstract

Modifiers of cement systems with different compositions of functional groups of polymers were studied: carboxymethylcellulose, methylcellulose, polyvinyl alcohol, polyacrylamide. The results of studies of the influence of active ions on the viscosity of aqueous solutions of water-soluble polymers using viscometry methods are presented. The influence of the type and composition of functional groups of polymer additives on the resistance to calcium, sodium and potassium ions is analyzed. It is shown that in the presence of calcium, sodium or potassium ions in the liquid phase of cement solutions, it is possible to reduce the effectiveness of polymers as stabilizers of binding systems. The most resistant to electrolytes are polymers with dominated hydroxyl groups. The composition of functional groups of water-soluble polymers and the possibility of their interaction with various ions contained in cement, aggregate, filler, in the closing water, in the composition of soils have a decisive influence on the compatibility of the polymer and the binder, the properties of cement-polymer compositions. The principles of regulating the rheological and technological properties of cement-polymer compositions, deformations of dispersed systems by selecting the rational composition of the dispersed mixture, mineral and chemical additives are given. The regularities of compatibility of components of cement systems, mineral and chemical additives in order to increase the adhesion and strength characteristics of materials based on them in the development of compositions of masonry solutions, injection and other compositions for chemical fixing of soils, in individual housing construction, in order to carry out repair and restoration work to strengthen soil bases and stone structures are presented.