Thermochemical properties of new N,O-chelate Sc, Eu, and Tb complexes for OLED-devices

A new class of Sc, Eu, and Tb complexes with N,O-chelate ligands was synthesized for the first time. The mass spectra, thermogravimetric analysis, differential scanning calorimetry data, as well as the data on the saturated vapor pressure of the compounds were obtained. The main thermochemical parameters of the compounds were calculated.     

Study of thermochemical properties of diphenyl[dialkyl(alkyl)carbamoylmethyl]phosphine oxides

The synthesis and the studies of properties of diphenyl[dialkyl(alkyl)carbamoylmethyl]phosphine oxides by differential scanning calorimetry, mass spectrometry and Knudsen effusion method were performed. The thermodynamic parameters of melting and vaporization were calculated.     

The effect of schungite filler on the degree of crystallinity of polypropylene and polyethylene in ternary mixed composites

The effect of schungite filler with a carbon content of 39 wt % on the degree of crystallinity of polypropylene and polyethylene in mixed ternary composites is studied. The PP-to-PE volume ratios are 80: 20 and 50: 50. With an increase in the content of the schungite filler, the fraction of the crystalline phase in PP increases, although the degree of crystallinity of PE decreases; this behavior is related to the high affinity between polypropylene and schungite filler. The surface structure of the initial and schungite-loaded PP-PE materials of various compositions is studied via AFM. The surface structure of the above composites is shown to be different, and its specific features are dependent on the ratio between polymer components and on the order in which all components are introduced into the system.     

Effect of diisocyanate nature on the properties of cyclolinear polyureas containing azacrown ether groups

New cyclolinear polyureas based on a crown-containing diamine—1,10-diaza-18-crown-6—and organic diisocyanates of different natures (aliphatic, aromatic, and alicyclic compounds) and an oligomeric diisocyanate have been synthesized. It has been found that, unlike most polyureas, azacrown-containing polymers are soluble in a wide variety of organic solvents. The calorimetric and mechanical properties of these polymers in dry and equilibrium-swollen states have been studied. It has been shown that the basic characteristics of these cyclolinear systems can be tailored by varying the nature of the diisocyanate used.     

Effect of stereoregularity on the structure and thermophysical characteristics of isotactic polypropylene

The structure, thermophysical, and thermomechanical characteristics of metallocene-synthesized isotactic PPs of different molecular masses containing different amounts of stereodefects have been studied. The degree of crystallinity and the content of a and g modifications in slowly cooled and melt quenched films are estimated by three independent methods, i.e., X-ray analysis, DSC, macroscopic density measurements, and changes in their phase structure upon annealing and orientation are analyzed. As the content of stereodefects increases, the fraction of g crystallites in the films increases, while the degree of crystallinity decreases (down to 5%). The formation of the g phase is assumed to be related to the epitaxial crystallization; this process is assisted by stresses induced on chains upon slow melt crystallization and after annealing of the oriented samples. This evidence allows the analysis of structural and thermodynamic characteristics of thermoplastic and elastic samples of the isotactic PP.