Spray emulsion polymerization

Han, Y.K., Yih, J.N., Chang, M.Y., Huang, W.Y., Ho, K.S., Hsieh, T.H., Lou, J.G., 2011. Facile synthesis of aqueous-dispersible nano-PEDOT PSS-co-MA core/shell colloids through spray emulsion polymerization. Macromol. Chem. Phys. 212,361-366. 

Since the 1940s, alkanesulfonates have served as emulsifiers in the emulsion polymerization of vinylchloride. Nevertheless, the detailed mechanisms of this process are not yet completely known. An important advantage of using alkanesulfonates is that they produce latices with a high solid content, which can be effectively processed by spray drying [90]. 

The polymer in emulsion polymerization is isolated by either coagulating or spray drying. 

Emulsion Polymerization. Emulsion polymerization takes place in a soap micelle where a small amount of monomer dissolves in the micelle. The initiator is water-soluble. Polymerization takes place when the radical enters the monomer-swollen micelle. Termination takes place in the growing micelle by the usual radical-radical interactions, The high solubility of vinyl chloride in water, 0.6 wt %. accounts for a strong deviation from true emulsion behavior. Also, PVC s insolubility in its own monomer accounts for such behavior as a rate dependence on conversion. Emulsions of up to 0.2- im dia are sold in liquid form for water-based paints, printing inks, and finishes for paper and fabric. Other versions, 0.3-10- j.m dia and dried by spray-drying or coagulation, are used as plastisol resins. 

The final product of an emulsion polymerization is referred to as latex. Emulsion polymerization products can in some instances be employed directly without further separations but with appropriate blending operations. Such applications involve coatings, finishes, floor polishes, and paints. Solid polymer can be recovered from the latex by various techniques such as spray drying, coagulation by adding an acid, usually sulfuric acid, or by adding electrolyte salts. 

Dispersion Resins. These materials used in plastisols or organosols have a very fine particle size, in the range of 0.1 to 2 Um and are made by emulsion polymerization followed by spray drying. 

In spray dryers, the feed material, in the form of a solution, suspension, slurry, or paste, is sprayed in a high-tanperature gas zone by centrifugal disks or pressure nozzles. Such dryers are used in polymer industries in which the polymers cannot be separated mechanically from the carrier liquid, e.g., emulsion-polymerized PVC. 

Uses Thickener, dispersant, foam stabilizer, coupling agent for emulsion polymerization, pesticides, petrol, prod., h vy-duty liq. detergents, adhesives, coatings, pharmaceutic s film-former in spray bandages complexing agent for sustained-release iron preps. ostomy adhesives denture adhesives/stabilizers dentifrices thickener for aq. or org. solv. sterns... 

Chem. Descrip. Sodium dioctyl sulfosuccinate CAS 577-11-7 EINECS/ELINCS 209-406-4 Uses Surfactant, wetting agent for adhesives, flexo and gravure inks, paints, high-gloss paints, paper, textiles, emulsion polymerization, agric. sprays... 

CAS 9016-45-9 EINECS/ELINCS 248-293-6 Uses Detergent, wetting agent, emulsifier, dispersant, solubilizer for concrete mfg., agric. sprays, pesticides, solv. cleaners, paints, detergents, emulsion polymerization, leather, textiles, pulp/paper base surfactant for household and industrial detergents Properties Hazen 100 liq. sol. in water, benzene, ethyl acetate, ethyl Icinol, perchlorethylene, ethanol, veg. oil, olein sp.gr. 1.056 vise. 350 cps m.p. 0 2 C HEB 12.3 cloud pt. 30-34 C pH 6-8 (1% aq.) surf, tens. 29.4 dynes/cm (0.1%) wetting 4.1 s (0.1%) Ross-Miles foam 6.7 cm (0.1%, initial) nonionic 100% act. 

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