The aim of the thesis is to present reversibly crosslinked polyurethanes with an aromatic pinacol unit containing a reversible C-C bond. In the study in question, the scientists synthesized PU based on pinacol (P1) and synthesized and tested similar polyurethanes (P2, P3) to confirm the properties of P1, but they differ in composition and properties. The high toughness of pinacol-based PUs is attributed to the high energy of the C-C bond, which decreases with bond length due to electronic and steric effects. Under moderate conditions (appropriate bond cleavage activation energy), the bonds in a pinacol-based PU can split and reconnect. Mixing and rearranging the nets leads to the healing of the cracks. The glass transition temperature of polyurethane P1 was determined by dynamic mechanical analysis (DMA) through the calculation of the modulus (elastic E', viscous E'') of the material and tan δ. It was found that no temperature control is required for reversible P1 reaction treatment. The most important step in the synthesis of the stimulus-responsive polymer P1 was the preliminary synthesis of hydroxy-functionalized aromatic pinacol and its incorporation into cross-linked polyurethane.
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