The use of superabsorbent polymers (SAP) in construction is a relatively new trend, and not a completely explored area. However, SAP itself has been on the market for over 80 years. SAPs have a cross-linked three-dimensional structure, thanks to which they have the unique ability to absorb extreme amounts of water, up to a hundred times their weight. By using this property, it is possible to prevent water losses, which is important at the time of maturation in cementitious building materials. When there is a lack of water needed for hydration processes, the physical and mechanical properties deteriorate. The subject of this article is to determine the possible positive effect of the presence of SAP in the cement matrix in order to optimize the parameters of silicate composites for 3D printing. For this purpose, a special methodology was compiled consisting of tests through which it is possible to assess the suitability of the tested mixtures for 3D printing. This methodology consists of determining consistency, volumetric weight, ultrasonic analysis, buildability, X-ray diffraction, flexural tensile and compressive strength. For determining of buildability and ultrasonic analysis new methodologies were created in this research in order to be suitable for the 3D printing materials. Last but not least, efforts are also being made to increase the incorporation of secondary raw material (fly ash) in order to reduce the environmental impact of industrial production and, conversely, to increase its sustainability while maintaining or improving the mechanical–physical parameters of building materials. From the results presented in this paper it is apparent, that created methodology is efficient for determining properties of 3D printable mixtures. SAPs also significantly influenced properties of these mixtures. Mainly buildability and flexural tensile strength (by up to 30%) were increased and volumetric weight was decreased (by up to 5%).

Crystalline admixtures and industrial by-products can be used in cement-based materials in order to improve their mechanical properties. The research examined long-term curing and the exposure to environmental actions of polymer–cement mortars with crystalline admixture (CA) and different by-products, including Bengħisa fly ash and Globigerina limestone waste filler. The by-products were introduced as a percentage replacement of the cement. A crystallization additive was also added to the mixtures in order to monitor the improvement in durability properties. The mechanical properties of the mortar were assessed, with 20% replacement of cement with fly ash resulting in the highest compressive strength after 540 days. The performance was analyzed with respect to various properties including permeable porosity, capillary suction, rapid chloride ion penetration and chloride migration coefficient. It was noted that the addition of fly ash and crystalline admixture significantly reduced the chloride ion penetration into the structure of the polymer cement mortar, resulting in improved durability. A microstructure investigation was conducted on the samples through Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS). Crystals forming through the crystalline admixture in the porous structure of the material were clearly observed, contributing to the improved properties of the cement-based polymer mortar.

This paper describes the use of cement‐based waterproofing screed and waterproofing coating, in which 10% of the original amount of cement was replaced by fly ash and 2% of the crystallization admixture was added by weight of cement, as a mean of protection of concrete against aggressive environments. The modified materials were applied to the underlying concrete and subjected to testing of physical and mechanical properties after exposure to effects of aggressive environments for up to 18 months. The results of the analysis have shown that after the application of waterproofing materials, there is a sufficient development of the crystals in the underlying concrete to enhance its durability. Thus, it is possible to use fly ash functionally and efficiently in polymer cement systems as a substitute for the cement together with the crystallization admixture.

Phase change materials (PCMs) are materials with the ability of absorption of latent heat based on a phase change. PCMs are able to store and release a large amount of energy at certain temperatures melting or freezing. The aim of the research is to verify whether this phenomenon (material) can be used within an external thermal insulation composite system (ETICS). This is particularly the usage of PCMs in the base coat. The research is focused on two main areas. The first area concerns the water condensation on the surface of the ETICS and the associated phenomenon of algae attack. The second area concerns the warming of ETICSs with the use of dark color shades. Practical experiments showed a positive effect of PCMs on the heat-storage properties of the ETICS base coat. It was also experimentally verified that the PCM sample did not condense water vapor on the sample surface compared to the reference sample.

Crystallization of bisphenol A (DGEBA)- and bisphenol F (DGEBF)-based epoxy resins is a natural property of these oligomers. However, manufacturers of coatings and other systems based on these epoxy resins are making efforts to slow down the crystallization process as much as possible, thereby extending the shelf life and improving the competitiveness of their products. This paper focuses on the kinetics of the crystallization process of epoxy resins and the effect of the presence of a certain degree of crystallinity on selected parameters of epoxy-based materials. Furthermore, an analysis of the impact of a certain degree of crystallinity of the epoxy base on the resulting coating parameters was carried out. The highest value of crystallinity (17%) was achieved in the sample containing the highest proportion of DGEBF in the crystallization phase “c”, and the enthalpy of melting (H_t) of the crystalline DGEBF sample was 6.3 J/g. Mechanical parameters as well as chemical and thermal resistance of hydrophobic epoxy systems were investigated. The best abrasion resistance (1.5 cm³/50 cm²) was achieved with the blend containing only amorphous DGEBA. The adhesion of the epoxy samples on concrete was greater than 6.5 MPa. The chemical resistance tests performed showed that, in general, the chemical resistance of epoxy systems decreases with increasing crystallinity content. The tighter arrangement of molecules in the crystalline regions of the epoxy matrix results in an increase in density, strength and hardness. This study presents a comprehensive examination of the crystallization of DGEBA and DGEBF, which is, as yet virtually unavailable. It also contributes to knowledge by outlining the possibility of speeding up or slowing down the crystallization process of epoxy resins, including the principle of selecting nucleating agents.