A number of novel fluorophores have been synthesized containing an electron‐withdrawing pyrimidine core and electron donating N,N‐dimethylaminophenyl, 4‐(9H‐carbazol‐9‐yl)phenyl, phenyl and pyrrol‐1‐yl fragments at positions 2, 4 and 6 of the pyrimidine ring. Thermal, optical and electrochemical properties of these substances have been studied. The structure‐property dependences of substituted pyrimidines have been established.
In this work, new polymers with a shape memory effect for self-healing coatings based on oligomers with terminal epoxy groups, synthesized from oligotetramethylene oxide dioles of various molecular weights, were developed. For this purpose, a simple and efficient method for the synthesis of oligoetherdiamines with a high yield of the product, close to 94%, was developed. Oligodiol was treated with acrylic acid in the presence of a catalyst, followed by the reaction of the reaction product with aminoethylpiperazine. This synthetic route can easily be upscaled. The resulting products can be used as hardeners for oligomers with terminal epoxy groups synthesized from cyclic and cycloaliphatic diisocyanates. The effect of the molecular weight of newly synthesized diamines on the thermal and mechanical properties of urethane-containing polymers has been studied. Elastomers synthesized from isophorone diisocyanate showed excellent shape fixity and shape recovery ratios of >95% and >94%, respectively.
The effect of polyester oligoethylene adipate molecular weight, diisocyanate structure, and chain extender on the properties of epoxyurethane-based oligomer elastomers was studied in this research. Oligoethylene adipates were obtained via polycondensation of adipic acid and ethylene glycol. Epoxyurethane oligomers were synthesized according to a two-step route with an oligodiisocyanate as an intermediate product. The elastomers with hard urethane hydroxyl blocks were synthesized from oligodiisocyanates. The deformation and strength properties of the elastomers were studied.
2,4,6-Triphenylpyrimidine derivatives have been synthesized from the corresponding aromatic aldehydes and methyl ketones via a two-step procedure, which include an aldolcrotonic condensation followed by the reaction of the resulting chalcones with ammonium acetate in the presence of a catalytic amount of trifluoromethanesulfonic acid with DMF as a solvent The compound structures have been identified by NMR and IR spectroscopy and elemental analysis. The thermal, optical and electrochemical properties of the compounds obtained have been studied. The synthesized 2,4,6-triphenylpyrimidines are characterized by blue emission. It has been shown, that these compounds have narrow band gaps and high fluorescence quantum yields.
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