Synthesis of an inorganic-organic polymer blend from orthoboric acid and caprolactam

The possibility of modifying boron polyoxide with an oligomeric amide upon thermal dehydration of orthoboric acid and oligomerization of caprolactam in a common melt is shown. The products obtained after thermal pretreatment of the initial blend containing 30 wt % caprolactam are investigated. It is shown that the main processes at T < 200°C are dehydration of orthoboric acid and hydrolysis of caprolactam with the formation of ε-aminocaproic acid. At temperatures of 225–260°C, the predominant process is the formation of boron polyoxide and a caprolactam-based oligomeric product. The data of ¹¹B NMR spectroscopy show that the chemical transformations of caprolactam occur against the background of the N:B donor-acceptor interaction. The two-dimensional [¹¹B-¹H] heteronuclear correlation spectrum indicates that the systems obtained upon thermal treatment are solid solutions.     

High-performance liquid chromatographic determination of BRB-I-28, a novel antiarrhythmic agent, in dog plasma and urine.

A sensitive reversed-phase high-performance liquid chromatographic (HPLC) technique with ultraviolet detection has been developed to determine the concentration of BRB-I-28 (I), a novel antiarrhythmic agent, in dog plasma and urine. The mobile phase was acetonitrile-methanol-37.5 mM phosphate buffer, pH 6.8-triethylamine (50:50:75:0.1, v/v). The compound was extracted from dog plasma and urine with chloroform after alkalinization with sodium hydroxide. The extraction recovery was 83% from plasma and 84% from urine. Good linearity (r > 0.996) was observed throughout the ranges 0.1-12.0 micrograms/ml (plasma) and 0.1-8.0 micrograms/ml (urine). Intra- and inter-assay variabilities were less than 4%. The lower limit of quantitation was 0.08 microgram/ml in either plasma or urine. HPLC analysis of plasma and urine samples from a dog treated with I has demonstrated that the method was accurate and reproducible.     

Synthesis ofω-substituted 3-alkylorotic acids

3-(-Phthalimidoalkyl)-5-carbethoxymethylenehydantoins were synthesized by the reaction of-phthalimidoalkylureas with ethyl oxalacetate and then converted to 3-(-aminoalkyl)orotic acids. Condensation of the latter with 6-chloropurine yielded 3-[-(6-purinylamino)alkyljorotic acids.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 397–399, March, 1971.     

[(C~8H~8)Y(μ-OC~6H~5)(THF)]~2的合成和晶体结构

本文用(C~8H~8)Y(μ-Cl)(THF)]~2与NaOC~6H~5以1:2摩尔比在四氢呋喃中反应, 合成了新的中性配合物[(C~8H~8)Y(μ-OC~6H~5)(THF)]~2, 经过分离, 在-30℃下培养得到无色晶体, 用元素分析, 核磁共振和质谱进行了鉴定, 并以X-射线衍射测定了晶体结构。     

Synthesis and Properties of Copolymers Having Polyconjugated Blocks in the Macromolecules. III Thermal Behavior of Polyisoprene-Containing Polyazophenylene Fragments in the Main Chains

The thermal and thermooxidative stability of polyisoprene containing polyazophenylene fragments of different composition was investigated. Elevated inhibiting activity of polyazophenylene -methane fragments was found to be caused by the intramolecular synergism due to the combination of the reaction of peroxy radicals with mobile hydrogen atoms of methylene bridge groups and decomposition of hydroperoxides under the influence of polyconjugated blocks.     

Kinetic approach to modeling the radical polymerization of styrene in the presence dibenzyl trithiocarbonate

A mathematical model of the kinetics of the radical polymerization of styrene in the presence of dibenzyl trithiocarbonate by the reversible addition-fragmentation chain transfer mechanism with cross-termination of radicals and intermediates and quadratic termination of intermediates is developed. The adequacy of the polymerization mechanism underlying the model and the related mathematical formalism are tested by comparing the calculated and measured values of the average molecular-weight characteristics of resulting polystyrene.     

The influence of a fluoroorganic modifier—stillage residues of alcohol-telomeres—on properties of filled poldienurethanes

The results of an investigation of the influence of stillage residues of polyfluorinated alcoholtelomeres on the properties of polydienurethane compositions and elastomers based on them are presented. It is shown that such modification allows one to raise the sedimentation stability of the compositions and increase the characteristics of physicochemical and dynamic properties of elastomers.     

Chain Paramagnetic Processes and the Nature of Paramagnetic Centers of Polymers with Conjugated Systems

This paper is concerned with analysis of the basic regularities of the kinetics of formation of polymers with a conjugated system. The experimentally found regularities are explained in terms of the proposed chain branched polymerization mechanism. The principal role in the chain polymerization mechanism is played by paramagnetic centers which are formed from the diamagnetic macromolecules of the polymer in the process of synthesis. The formation of paramagnetic centers is also due to the chain mechanism. It has been established that the thermal effect of the reaction leads to localized overheating of the emerging heterophase of the polymer, which has important consequences for the kinetics of polymerization and the rate of formation of paramagnetic centers.