Degradation of Copolymers of N-Vinylpyrrolidone with Sodium 2-Acrylamido-2-Methylpropanesulfonate in Aqueous Solutions

The kinetics of controllable degradation of N-vinylpyrrolidone-sodium 2-acrylamido-2-methylpropanesulfonate copolymers in aqueous solutions under the action of degrading agents at 25-50°C were studied by viscometry. The efficiency of controlling the molecular weight of copolymer was estimated.     

Kinetics of Radical Copolymerization of Acrylamide with Magnesium 2-Acrylamido-2-Methylpropanesulfonate in Aqueous Solutions

Kinetic features of homogeneous radical copolymerization of acrylamide with magnesium 2-acrylamido-2-methylpropanesulfonate in concentrated aqueous solutions in the presence of the initiating system potassium peroxosulfate-sodium hydrosulfite at pH 9 and 50°C were studied by dilatometric technique.     

Copolymerization of Acrylamide with Sodium 2-Acrylamido-2-methylpropanesulfonate in Aqueous Salt Solutions

The kinetics of radical copolymerization of acrylamide with sodium 2-acrylamido-2-methylpropanesulfonate in water and in 1 M NaCl solutions at pH 9 and 30-50°C was studied. The kinetic data were interpreted with account of the state of the ionic groups and conformations of growing polymeric chains in the reaction mixtures.     

Kinetics of Thermal Degradation of Copolymers of Acrylamide with Sodium Acrylate in Aqueous Solutions

The kinetics of thermal degradation of commercial samples of copolymers of acrylamide with sodium acrylate of various molecular characteristics in water and 1.5% NaCl aqueous solutions at 40–80°C was studied viscometrically.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 6, 2005, pp. 1016–1020.Original Russian Text Copyright © 2005 by V. Kurenkov, Trofimov, A. Kurenkov, Khartan, Lobanov.     

Degree of Binding of Double-Charged Cations in Solutions of 2-Acrylamido-2-Methylpropanesulfonate Copolymers

The degree of binding of Mg^{2 +}, Ca²⁺, Sr²⁺, and Ba²⁺ cations with polysulfonate anions in aqueous solutions of 2-acrylamido-2-methylpropanesulfonate polymers and their binary mixtures with acrylamide and N-vinylpyrrolidone with various molecular characteristics was studied by the Terayama-Wall viscometric procedure.     

Radiation Crosslinking of an Acrylamide–Sodium Acrylate Copolymer in Aqueous Solutions

The effect of concentration of an acrylamide–sodium acrylate copolymer in an aqueous solution on the crosslinking of macromolecules by the action of ionizing radiation was studied. It was shown that the efficiency of radiation crosslinking of the copolymer increased with an increase in the concentration of solution subject to irradiation, which was tentatively explained in terms of the existence of fluctuative entanglement network ensuring the approaching of macroradical sites and, thus, facilitating the combination reactions of macroradicals.     

Water-Soluble Copolymers. XLI. Copolymers of Acrylamide and Sodium 3-Acrylamido-3-methylbutanoate

Copolymers of acrylamide (AM, M ₁) with sodium 3-acrylamido-3-methylbutanoate (NaAMB, M ₂) synthesized in 1 M NaCl (the ABAM2 series) are compared to those synthesized in deionized water (the ABAM1 series). At fixed feed ratios, higher incorporation rates were found for NaAMB with increasing ionic strength of the polymerization solvent. Reactivity ratios calculated by the methods of Kelen-Tüdös changed from r ₁ = 1.23 and r ₂ = 0.50 in deionized water to r ₁ = 1.00 and r ₂ = 0.64 in 1 M NaCl. This change is in accord with a decrease in electrostatic repulsion between the macroradical and unreacted NaAMB. Dilute solution properties, examined as a function of composition and added electrolytes, indicate differences in microstructure for the ABAM1 and ABAM2 copolymers.     

Degradation of Metal 2-Acrylamido-2-methylpropanesulfonate-N-Vinylpyrrolidine Copolymers in Aqueous Solutions Containing Different Cations

The influence of single- and double-charged cations on degradation of metal 2-acrylamido-2-methylpropanesulfonate-N-vinylpyrrolidine copolymers in aqueous solutions in the presence of potassium peroxodisulfate, K₂S₂O₈, at 50 and 70°C was studied by viscosimetry.     

Copolymerization of Sodium 2-Acrylamido-2-methylpropane-1-sulfonate with N-Vinylpyrrolidone in Aqueous Dimethylformamide Solutions

The kinetics of radical copolymerization of sodium 2-acrylamido-2-methylpropane-1-sulfonate with N-vinylpyrrolidone in water, water-dimethylformamide (1 : 1) solutions, and dimethylformamide at pH 9 and 60°C in the presence of initiators [azobis(isobutyronitrile) and ammonium persulfate] was studied by dilatometry.     

Effect of Alkali Metal Cation on Copolymerization of Acrylamide with Salts of 2-Acrylamido-2-methylpropanesulfonic Acid in Aqueous Solutions

The kinetics of radical copolymerization of acrylamide with lithium, sodium, and potassium 2-acrylamido-2-methylpropanesulfonates in concentrated aqueous solutions in the presence of potassium persulfate as initiating agent at pH 9 and 50°C was studied by dilatometry.     

Thermal Properties of Copolymers of Sodium 2-Acrylamido-2-methylpropanesulfonate with N-Vinylpyrrolidone

Thermal transformations of sodium 2-acrylamido-2-methylpropanesulfonate-N-vinylpyrrolidone copolymers of various chemical compositions were studied by thermogravimetric, differential thermal, and thermomechanical analyses within 20-600°C in air. The thermal degradation parameters in various temperature ranges were estimated, as well as the heat resistance of the copolymers.     

Radical Copolymerization of Sodium 2-Acrylamido-2-methyl-2-propanesulfonate with N-Vinyl-2-pyrrolidone in Water and Aqueous Salt Solutions

Features of homogeneous radical copolymerization of sodium 2-acrylamido-2-methyl-2-propanesulfonate with N-vinyl-2-pyrrolidone in water and aqueous NaCl solutions at pH 9 and 50°C, initiated with the redox system potassium peroxomonosulfate K₂SO₅-sodium pyrosulfite Na₂S₂O₅ were studied dilatometrically.     

Copolymerization of Magnesium and Calcium 2-Acrylamido-2-methylpropanesulfonates with N-Vinylpyrrolidone in Aqueous Solutions

The kinetics of radical copolymerization of magnesium and calcium 2-acrylamido-2-methylpropanesulfonates with N-vinylpyrrolidone in aqueous solutions at pH 9 and 50°C in the presence of an initiator, potassium peroxodisulfate, were studied dilatometrically, and the molecular characteristics of the resulting copolymers were determined.     

Copolymerization of Acrylamide with Salts of 2-Acrylamido-2-methylpropanesulfic Acid in Aqueous Solutions as Influenced by the Nature of Double-Charged Cation

The kinetics of copolymerization of acrylamide with magnesium, calcium, and strontium 2-acryl-amido-2-methylpropanesulfonates in aqueous solutions in the presence of potassium persulfate-sodium hydrosulfite initiating redox system at pH 9 and 50°C was studied as influenced by the cation nature.     

Spontaneous Polymerization of 2-Acrylamido-2-methylpropanesulfonic Acid in Acidic Aqueous Solutions

Spontaneous polymerization of 2-acrylamido-2-methylpropanesulfonic acid in the presence of inorganic and organic neutralizing agents in concentrated aqueous solutions is studied. The hypothesis of redox mechanism of the process initiation is discussed.     

丙烯酰胺－丙烯酸甲酯－2－丙烯酰胺基－2－甲基丙磺酸共聚物的合成及表征

以丙烯酰胺（ＡＭ），丙烯酸甲酯（ＭＡ）和２－丙烯酰胺基－２－甲基丙磺酸（ＡＭＰＳ）为原料，通过水溶液共聚，合成了一种新的三元共聚物。研究了影响共聚反应的因素，并对其结构进行了表征。     

Influence of Concentration and Molecular Characteristics of Copolymers of Acrylamide with Sodium Acrylate on the Thoms Effect in Oil-in-Water Emulsions

The effect of the concentration and molecular parameters of random copolymers of acrylamide and sodium acrylate on their performance as additives reducing the hydraulic resistance of turbulent flows in oil-in-water emulsions is quantitatively studied.     

(丙烯酰胺-丙烯酸十六酯)共聚物的合成及其增稠性能研究

采用沉淀聚合法合成丙烯酰胺 -丙烯酸十六酯共聚物。重点讨论了合成条件如单体配比、引发剂用量、温度等对共聚反应的影响以及共聚物对苯丙乳胶的增稠性能的影响。并用DMTA和凯达尔定氮法表征了共聚物组成 ,结果表明 :所合成的共聚物可以作为疏水缔合型增稠剂使用     

Altering Phase Separation in Aqueous Nonionic Surfactant Solutions by Power Ultrasound

Cloud point extraction (CPE) is an efficient and green separation technology as an alternative to conventional organic solvent extractions. How to accelerate the phase separation of aqueous surfactant solutions conveniently is of great importance. In this study, the effect of power ultrasound on the phase separation of aqueous solutions of a nonionic surfactant, Triton X-114 [(1,1,3,3-tetramethylbutyl) phenyl-polyethylene glycol], has been studied as a function of temperature by means of rheo-small angle light scattering. It is found that anomalous viscosity enhancements and micron-sized scattering aggregates are observed for the surfactant solutions after ultrasound irradiation. The aggregate growth is quantified by the characteristic length of the aggregates. It is proposed that ultrasonic cavitation can promote the aggregation or transition of surfactants in the aqueous solutions, resulting in the formation of micrometer-scale phase-separated droplets. This work may advance further understanding of the controlled transformation of aggregates in surfactant solutions via power ultrasound and promote its applications in CPE.