Sodium p-vinylbenzene sulfonate

In an inverse emulsion polymerization, a hydrophilic monomer, frequently in aqueous solution, is emulsified in a continuous oil phase using a water-in-oil emulsifier and polymerized using either an oil-soluble or water-soluble initiator the products are viscous latices comprised of submicroscopic, water-swollen, hydrophilic polymer particles colloidally suspended in the continuous oil phase. The average particle sizes of these latices are as small as 0.05 microns. The technique is applicable to a wide variety of hydrophilic monomers and oil media. The inverse emulsion polymerization of sodium p-vinylbenzene sulfonate initiated by both benzoyl peroxide and potassium persulfate was compared to the persulfate-initiated polymerization in aqueous solution. Hypotheses for the mechanism and kinetics of polymerization were developed and used to calculate the various kinetic parameters of this monomer. 

General. Aqueous solutions of hydrophilic monomers were emulsified in xylene using water-in-oil emulsifiers, and polymerized using oil-soluble initiators. Typical hydrophilic monomers were sodium p-vinylbenzene sulfonate, sodium vinylbenzyl sulfonate, 2-sulfoethyl acrylate, acrylic acid, acrylamide, vinylbenzyl-trimethylammonium chloride, and 2-aminoethyl methacrylate hydrochloride. Typical oil-soluble initiators were benzoyl and lauroyl peroxides. In some cases, water-soluble potassium persulfate was used, both separately and in mixtures with oil-soluble peroxides. Of the water-in-oil emulsifiers, one of the most effective was Span 60 (technical sorbitan monostearate. Atlas Chemical Industries, Inc.). 

The basis for the kinetic mechanisms of inverse emulsion polymerization can be found in the seminal woik of Vanderhoff et al. published in 1962 which dealt with the polymerization of sodium p-vinylbenzene sulfonate in xylene [26]. There was then a gap of almost two decades before new fundamental studies were reported, mainly motivated by the novel applications developed in the field of oil recovery processes. However, the results are in many respects contradictory and... 

These latices consist of submicroscopic, water-swollen, hydrophilic polymer spheres colloidally suspended in the continuous xylene phase. A typical electron micrograph of a diluted dispersion of a sodium poly (p-vinylbenzene sulfonate) latex which had been treated to remove water is shown in Figure 3. The inverse... 

Figure 3. Electron micrograph of sodium poly (p-vinylbenzene sulfonate) latex...

The final latices were prepared for electron microscopy by dilution with xylene to ca. 0.1% polymer followed by distillation to remove the water. The distilled latices were diluted further and dried on the specimen substrates. The electron microscope specimens could not be calibrated with monodisperse polystyrene particles because of the sensitivity of the sodium poly (p-vinylbenzene sulfonate) particles to water. Instead, the magnification was calibrated from one separate exposure of monodisperse spheres which was made on each photographic plate of five ejqjosures. 

Itsimo [25] has also shown that polymer-supported OPEN monosulfonamides containing sulfonated pendent group (Scheme 16) are able to catalyze the HTR reduction of ketones in water with sodium formiate as hydrogen donor (S/C = 100). However, TsDPEN immobilized on polystyrene crosslinked or not, polymer 30 and 31 respectively, shrank in water. Sodium /j-styrene sulfonate was copolymerized with chiral A-(vinylbenzene-p-sulfonyl)-DPEN (20) imder radical polymerization conditions with or without DVB leading respectively to ligand 32 and 33. Control of the balance hydrophilicity/hydrophobieity of the polymer support is carried out by changing the salt from Na to quaternary ammonium. All of these polymers swelled in water, and their respective ruthenium, rhodium or iridium complexes were prepared. Compared to sodium salt polymer-supported catalyst from 32a and 33a, ammonium... 

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