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Emulsifier-free Emulsion Copolymerization (emulsifier-free + emulsion_copolymerization)
Selected AbstractsEmulsifier-Free Emulsion Copolymerization of Vinyl Acetate and 3-Dimethyl(methacryloyloxyethyl)ammonium Propanesulfonate and Swelling Behavior of their Copolymer MatricesMACROMOLECULAR REACTION ENGINEERING, Issue 5 2007Elena Kamenska Abstract Stable poly{(vinyl acetate)- co -[3-dimethyl(methacryloyloxyethyl)ammonium propanesulfonate]} latexes with different compositions were synthesized by emulsifier-free emulsion copolymerization. An unusual "overshooting" behavior of the copolymer tablets is explained based on the formation of specific clusters of oppositely oriented dipoles. The variation of their concentration with the zwitterionic monomer unit fraction, ionic strength and temperature is responsible for the differences in the swelling kinetics established. The results show that these parameters can be used to control swelling degree of copolymer matrices and their sustained drug delivery. [source] Effect of the carboxylic acid monomer type on the emulsifier-free emulsion copolymerization of styrene and butadieneJOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2007Mahdi Abdollahi Abstract Carboxylated styrene,butadiene rubber latexes were prepared through the emulsifier-free emulsion copolymerization of styrene and butadiene with various carboxylic acid monomers. The effects of various carboxylic acid monomers on the particle formation process were investigated. The type of carboxylic acid monomer strongly affected the particle nucleation. The number of particles and thus the polymerization rate increased with the increasing hydrophobicity of the carboxylic acid monomers. There was a significant difference in the polymerization rate per particle. The results showed that particle nucleation and growth were dependent on the hydrophilic nature of the carboxylic acid monomers. The average particle diameter of the carboxylated styrene,butadiene rubber latexes in the dry state was obtained through some calculations using direct measurements of the average particle diameter in the monomer-swollen state by a dynamic light scattering technique. Several parameters, such as the polymerization rate, number of latex particles per unit of volume of the aqueous phase, and polymerization rate per particle, were calculated. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source] Principle of a New Immunoassay Based on Electrophoretic Mobility of Poly(styrene/, - tert -butoxy- , -vinylbenzyl-polyglycidol) Microspheres: Application for the Determination of Helicobacter pylori IgG in Blood SerumMACROMOLECULAR BIOSCIENCE, Issue 1 2005Teresa Basinska Abstract Summary: The principle of a novel latex diagnostic test for the determination of antibodies against Helicobacter pylori in blood sera is described. The test is based on the measurement of the electrophoretic mobility of the microspheres with immobilized H. pylori antigens. The electrophoretic mobility of these microspheres depends on the concentration of the antibodies against H. pylori in suspending medium. Particles with hydrophilic polyglycidol in the surface layer were used for the test. The microspheres were obtained by an emulsifier-free emulsion copolymerization of styrene and , - tert -butoxy- , -vinylbenzyl-polyglycidol macromonomer (,=,220 nm, diameter polydispersity factor ,=,1.02). Activation of polyglycidol hydroxyl groups with cyanuric chloride allowed for covalent immobilization of H. pylori antigens. The fraction of H. pylori not specifically adsorbed onto the microspheres was negligible. Changes of the electrophoretic mobility of the microspheres with the surface concentration of the covalently immobilized H. pylori antigens ,,=,(1.6,±,0.3),·,10,3 g m,2 were suitable for the detection of the antibodies in the sera of patients with titer in the range (determined by the indirect ELISA test) from 1:500 to 1:32,000. [source] Emulsifier-Free Emulsion Copolymerization of Vinyl Acetate and 3-Dimethyl(methacryloyloxyethyl)ammonium Propanesulfonate and Swelling Behavior of their Copolymer MatricesMACROMOLECULAR REACTION ENGINEERING, Issue 5 2007Elena Kamenska Abstract Stable poly{(vinyl acetate)- co -[3-dimethyl(methacryloyloxyethyl)ammonium propanesulfonate]} latexes with different compositions were synthesized by emulsifier-free emulsion copolymerization. An unusual "overshooting" behavior of the copolymer tablets is explained based on the formation of specific clusters of oppositely oriented dipoles. The variation of their concentration with the zwitterionic monomer unit fraction, ionic strength and temperature is responsible for the differences in the swelling kinetics established. The results show that these parameters can be used to control swelling degree of copolymer matrices and their sustained drug delivery. [source] | ||||||||||