This paper presents chosen results of extensive research conducted on strain and compressive strength of concrete with admixtures causing expansion. The efficiency was tested with use of two commercially available products: MC-Einpresshilfe and Expancrete, as well as self developed, according to own recipe. Own apparatus was designed and presented, which was used for the strain study of concrete. From the tested admixtures, only Expancrete MAPEI allowed to obtain expansive concrete. Other used admixtures - MC-Einpresshilfe and composition of gypsum, lime and kaolin cannot be used to obtain expansive concrete. However, they can reduce concretes shrinkage.
In this work, the results of investigations of polyurethane materials were presented. Innovative materials based on polyurethane-polyisocyanurate (PUR/PIR) foam were obtained. Different types of additives (flame retardants, aerogels – additives that decrease thermal conductivity) are used in the composition of PUR/PIR foam. Foams are a type of composite composed of two phases: continuous (polyurethane polymers) and dispersed (composed of gases). All samples have been tested for thermal parameters: thermal conductivity, specific heat, and thermal diffusivity. Then they have been compared with each other and with a reference sample (RS) without additives. Based on the research, it was shown that innovative insulation materials were characterized by thermal conductivity λ in the range of 0.0254–0.0294 W/(m · K). The thermal properties of foams depending on the type and chemical composition of the material. Depending on the used substrates, their molar ratio, type, synthesis conditions, modifying agents and catalysts, a different polyurethane material is obtained.
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