This paper presents the results of research on the influence of polymer modifiers: styrene-acrylic copolymer, vinyl acetate/ethylene (EVA), vinyl acetate/acrylic copolymer (VAAc), and VA/VeoVa/acrylic terpolymer on the water permeability and adhesion of cement-containing waterproofing mortars in concrete. The content of the polymers in the composition of the mortars was 15, 20 and 26% (m/m) in relation to the weight of the dry ingredients. Using microscopic methods, an attempt was made to analyse the relationship between the microstructure of the mortars and the properties of these polymers. The EVA and the vinyl acetate/acrylic copolymer, which were used in the form of dry powders, had the most favourable effect on water permeability and adhesion to the concrete substrate. They may prove to be useful for the production of one-component cement-containing waterproofing mortars. On the other hand, the VA/VeoVa/acrylic terpolymer modifier had the least favourable effect on the tested properties. For mortars with this modifier, the desired water-permeability parameters were not achieved. Depending on the amount of polymer modifier, the mortars were characterized by differences in watertightness, as established on the basis of changes in porosity and differences in the adhesion of the cement-polymer paste to the surface of aggregate grains. It was determined that the type of polymer and its dispergation properties influence the water permeability of mortars, as well as their adhesion to concrete substrates.

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The article attempts to assess the possibility of using non-woven fabrics made of waste fibers in cladding panels. For this purpose, woolen and polypropylene nonwovens were tested for mass per unit area, characteristic opening size, and lengthwise and crosswise elongation at maximum strength. Non-woven fabrics were placed in the middle of the thickness of cement and gypsum boards and subjected to tests of density, thermal conductivity coefficient λ, and bending strength. The influence of individual nonwoven fabrics with different properties on the properties of the finished composite was determined. It was found that wool nonwoven fabrics had the best effect on the thermal conductivity coefficient. A better affinity for nonwoven fabrics was shown by gypsum mortar. The best influence on the bending strength of the panels had polyester non-woven fabrics with the lowest mass per unit area and the largest characteristic opening size.