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481.
Andrey A. Prishchenko Mikhail V. Livantsov Olga P. Novikova Ludmila I. Livantsova Gleb M. Averochkin Valery S. Petrosyan 《Heteroatom Chemistry》2015,26(6):405-410
The convenient methods for the synthesis of new trimethylsilyl esters of aminomethylenediphosphonic acids are elaborated. The new substituted N‐formylaminomethylenediphosphonates are obtained via the interaction of trimethylsilyl esters of methylenediphosphonic acids with a mixture of triethyl orthoformate and ethanol. Also boron trifluoride–diethyl etherate as an effective catalyst is used for the interaction of hydrochlorides of ethoxymethylene imines with diethyl trimethylsilyl phosphite. The corresponding aminomethylenediphosphonic acids are presented. 相似文献
482.
Sruthy Baburaj Jayachandran Parthiban Sarvar Aminovich Rakhimov Rasheedah Johnson Ludmila Sukhomlinova Paul Luchette Steffen Jockusch Malcolm D. E. Forbes Jayaraman Sivaguru 《Photochemistry and photobiology》2023,99(3):901-905
The study evaluates compatibility of stabilizers with dye doped liquid crystal (LC) scaffolds that are used in electronically dimmable materials. The photodegradation of the materials was investigated and suitable stabilizers were evaluated to slow the degradation process. Various types of benzotriazole-based stabilizers were evaluated for stabilizing the liquid crystals. Based on spin trapping experiments, radicals generated upon UV exposure is likely responsible for the degradation of the system. The radical generation is competitively inhibited by the addition of stabilizers. 相似文献
483.
Petra Volfova Viera Chrastova Ludmila Cernakova Juraj Mrenica Janka Kozankova 《Macromolecular Symposia》2001,170(1):283-290
Polystyrene/poly(butyl acrylate) PS/PBA polymer dispersions with core/shell particles functionalized by N‐methylol acrylamide (N‐MA) were prepared through two‐step emulsion polymerization. The influence of N‐MA situated in shell and/or in core/shell of particles on the crosslinking reaction was studied to relate its mechanical properties and organic solvent resistance of films cast from basic and modified PS/PBA latexes. The changes in the phase arrangement of functionalized and unfunctionalized films after treatment with solvent and annealing were monitored. It was found that at the presence of N‐MA the crosslinking reaction occured already during the polymerization. Films from functionalized dispersions exhibit improved tensile strength and higher resistance against organic solvent. 相似文献
484.
Andrey A. Prishchenko Mikhail V. Livantsov Olga P. Novikova Ludmila I. Livantsova Valery S. Petrosyan 《Heteroatom Chemistry》2016,27(6):381-388
The convenient syntheses of new aryl‐substituted hydroxymethylphosphonic and methylenediphosphonic acids from the aromatic aldehydes, their derivatives, and phosphorous acid esters in the presence of the effective catalysts (trimethylsilyl trifluoromethanesulfonate, zinc chloride, and cadmium iodide) were developed. 相似文献
485.
486.
Vladislav Yu. Kudrya Valeriy M. Yashchuk Ludmila P. Paskal Tetyana B. Zheltonozhskaya Ol'ga V. Demchenko 《Macromolecular Symposia》2001,166(1):249-254
Sorbtion of some impurities from aqueous solutions by polymer complex poly(vinylalcohol) with poly(acrylamide) grafted copolymers (PVA‐PAAN) was studied by means of spectrophotometry and steady‐state fluorescence methods. The experiments showed that the PVA‐PAAN films effectively sorbs impurities molecules of average benzene ring from water. Simultaneously, the processes of polymer films dissolving in water take place. The thermal annealing (with the help of special methods) PVA‐PAAN film gives a possibility to obtain non‐dissolving polymer films which possess high sorbtion ability. Such films are proposed to be used as the sensors with optical response. 相似文献
487.
488.
Alexander V. Yakimansky Ludmila V. Vinogradova Boris L. Erussalimsky 《Macromolecular theory and simulations》1994,3(3):633-637
The energetic and electronic parameters of various mono- and bidentate complexes of CH3Li with N- and O-containing electron donors were calculated by the MNDO method. It was shown that N,N,N′,N′-tetramethylethylenediamine (TMD) forms a more stable bidentate complex with CH3Li than 1,2-dimethoxyethane (DME). However, DME, in contrast to TMD, may form a bis-bidentate complex with CH3Li in which the C Li bond is weakened to a higher degree than in complexes of CH3Li with N-containing electron donors. Much lower steric hindrance of DME, as compared to that of TMD, makes an easy formation of bis- and tris-monodentate complexes of DME with CH3Li possible; in these bis- and tris-monodentate complexes DME was simulated by (CH3)2O. Parameters of the C Li bond in the tris-monodentate complexes of (CH3)2O and tetrahydrofuran (THF) with CH3Li are comparable to those of the bis-bidentate complex CH3Li · 2 DME. These results are in qualitative agreement with experimental data, according to which THF and DME, in contrast to TMD, can favor the formation of separated ion pairs as active sites in anionic polymerization. 相似文献