Quantitative theory of living free‐radical polymerization. III. Calculation of copolymerization products' spinodal

The problem of finding conditions of the loss of thermodynamic stability by the reaction system was solved on the basis of the developed theory of living free‐radical copolymerization. The spinodal's calculations were carried out for a significant number of systems differing in the values of kinetic, stoichiometric, and thermodynamic parameters. Analysis of the results of such calculations revealed some regularities in the spinodal curves' behavior and permitted us to classify their possible topological types. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 892–902, 2003     

Calorimetric Method for the Investigation of Copolymerization Kinetics

Abstract

A calorimetric method for measurement of the copolymerization rate over a wide range of conversions has been derived. The well-known methyl methacrylate-styrene system was used as the example to prove the efficiency of the approach proposed.     

Configurational Effects in Statistical Theory of Branched Non-Random Polycondensation

The statistical theory of gelation in the simplest process of the non-random polycondensation (S. I. Kuchanov, T. V. Zharnikov, J. Stat. Phys., 111(5/6), 1273 (2003)) has been refined as to be able to take into account the effect of a monomer configuration on topological characteristics of the polymer network of the gel. Proceeding from the kinetic analysis of such a polycondensation, we rigorously prove that it can be described in terms of some stochastic branching process. The parameters of the process depend on the overall number of functional groups in the monomer as well as on the pattern of their mutual arrangement. Examples of some model systems illustrate the effect of kinetic and configurational factors on the topology of a polymer network formed in the course of non-random polycondensation.     

A lattice gas model for thermohydrodynamics

The lattice gas model is extended to include a temperature variable in order to study thermohydrodynamics, the combination of fluid dynamics and heat transfer. The compressible Navier-Stokes equations are derived using a Chapman-Enskog expansion. Heat conduction and convection problems are investigated, including Bénard convection. It is shown that the usual rescaling procedure can be avoided by controlling the temperature.     

Cyclization of N-alkylazinium cations with bisnucleophiles. 3. endo adducts in the reaction of quinoxalium salts with β-diketones and their x-ray diffraction analysis

The cyclization of N-alkylquinoxalinium salts with the anions of -dicarbonyl compounds proceeds regioselectively and stereoselectively and leads to endo-3a, 4,9,9a-tetrahydrofuro[2,3-b]quinoxalines. The structure of the cycloadducts was established on the basis of the ¹H and ¹³C NMR spectra and the results of x-ray diffraction analysis.See [1] for Communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1392–1398, October, 1981.