Functional Effectiveness of Hydrophobic Additives Based on PEGylated Hyperbranched Polymethylethoxysiloxane and Silicasol in Cement Systems

Concrete, as a building material, is strong and durable. However, under the influence of aggressive environmental factors, it can undergo corrosion and destruction. Water, in the form of precipitation and groundwater, is one such medium that can have a negative impact on concrete. Water is a weak solution of salts, acids, and bases, and it can lead to the deterioration of concrete structures. To prevent the negative effects of water on concrete, various additives are used. These additives help to increase the resistance of concrete to moisture. Among these additives, organosilicon‐based compounds are particularly effective. They have unique physicochemical properties and are economical to produce. However, the exact mechanism of their action is not fully understood. The aim of this research is to investigate the effect of a specific type of hydrophobic additive on the physical and mechanical properties of concrete. This additive is based on polymethylethoxysiloxane–polyethylene glycol (PMEOS–PEG) and silica sol in ethyl cellulose (silicasol). The results of the study will help to better understand the role of these additives in improving the durability of concrete structures under water‐related conditions. PMEOS–PEG has been shown to increase the mobility of the solvent mixture and also slightly increase the latency. Silicasol, on the other hand, does not affect mobility and has a significant retarding effect. The introduction of PMEOS–PEG hydrophobizer increases the strength of mixtures by 50%, when using Portland cement grade CEM II/A‐S 42.5 N, and by 20% in mixtures with unmodified Portland cement CEM I 42.5 N. Silicasol’s addition does not alter the strength characteristics of cement–sand mixtures. There is a slight tendency toward a decrease when using CEM I 42.5 N. The water impermeability of concrete samples using PMEOS–PEG and silicasol at a dosage of 0.7% increases from W6 (without additives) to W12 and W8, respectively.