Organosol dispersant

Vinyl organosol coatings, which incorporate a high molecular weight thermoplastic PVC organosol dispersion resin, are extremely flexible. Soluble thermosetting resins, including epoxy, phenoHc, and polyesters, are added to enhance the film s product resistance and adhesion. 

Other important forms of PVC include plastisols, which are dispersions of the polymer in a plasticizer, and organosols, dispersions of polymer, plasticizer, and a volatile solvent. Dispersions are produced by spray-drying the polymer mixture made by emulsion or suspension polymerization. The friable powder produced this way is milled and then mixed... 

Uses Solvent for baking enamels and printing inks coalescing aid for both architectural and industrial latex paints, and as an organosol dispersant Features High boiling... 

Plastics. Lecithin (0.5—1.5%) is used for pigment dispersion and as a shp or release agent. It also may be sprayed on molds. It has surfactant effects in organosols and plastisols (see Surfactants). 

In an organosol, the liquid constituent that displays solvating or peptizing action on the resin subsequent action aids in dispersing and suspending resin. 

Two-piece food cans may be made by a draw-redraw process, in which lacquer is first applied to and cured on sheet. Blanks are then cut from the sheet and the can is drawn from the blank in two or three stages. The lacquer deforms with the drawing process and lubricates the draw. It then becomes the interior protective coating. Although epoxy-phenolic solvent-borne lacquers are used, even better drawing properties are obtained from organosols. These are dispersions of colloidal polyvinyl chloride powder in solutions of other mixed resins in solvent, e.g. chosen from epoxy, polyester, vinyl and phenolic. 

In an emulsion, the oldest process. The presence of emulsifiers at a greater or lesser level gives a variable haze to the finished articles, eases the processing, decreases the electrostatic build-up, and increases the absorption of water. E-PVC, dispersion PVC or PVC pastes are used to make plastisols and organosols. 

Small particles (10 6 to 10 8 m range) dispersed in a liquid (hydrosols in water, organosols in an organic solvent) or gaseous (aerosol) medium. 

Another method, the emulsion process, was developed in Europe to meet the demand for a resin with small particle size, high bulk density, and low plasticizer absorption properties. These characteristics are especially desirable in making plastisols and organosols, where the resins are dispersed in liquid plasticizers. In this polymerization process, emulsifiers are added, and the solution is agitated to keep the monomer droplets dispersed. The initiators must be water soluble it is usually an inorganic persulfate or an organic hyperperoxide. 

ORGANOSOL. Colloidal dispersion of any insoluble material in an organic liquid specifically the finely divided or colloidal dispersion of a synthetic resin in plasticizer in which dispersion the volatile content exceeds 5% of the total,... 

PLASTISOL. A dispersion of finely divided resin in a plasticizer. Atypical composition is 100 parts resin and 50 parts plasticizer, forming a paste that gels when heated to 150C as a result of solvation of the resin particles by the plasticizer. If a volatile solvent is included, the plastisol is called an organosol. 

Because of the low level of emulsifiers and protective colloids, the suspension polymer types are most suitable for electrical applications and end uses requiring clarity, This form is also employed in the bulk of extrusion and molding applications. Cost is lower than for emulsion and solution forms. The emulsion or dispersion resins are employed mainly for organosol and plastisol applications where fast fusion with plasticizer at elevated temperature will occur as a result of the fine particle size of the resin. 

Commercial Plastisols, Accdg to definition given in Ref 2, a plastisol is a liquid dispersion of finely divided resin in a plasticizer. It is usually 100% solid with no volatiles when volatile content exceeds 5% of the total wt it is called organosol. When the plastisol is heated, the plasticizer solvates the resin particles, and the mass gels. With continued application of heat the mass fuses to become a conventional thermoplastic material... 

Key Q powdered resin compositions R = a(jueous latexes, emulsions, dispersions S- organic lacquer solutions and dispersions T - plastisol and organosol formulations U = natural and synthetic rubber compositions V = hot-melt compositions W = thermoplastic masses X = oleoresinous compositions Y = reading formulations, eg.. epoxy and polyester Z = plastic monomers Dry thickness-... 

Different methods of coating are used to meet different coated product requirements (Table 10.1). The coating materials are in different forms ranging from liquids to solids. They include emulsion, latex, dispersion, lacquer, powdered plastic composition, plastisol, organosol, rubber composition, hot-melt, reacting TS compound, etc. The product could be plastic film, paper, paperboard, woven fabric, plywood, nonwoven fabric, steel sheet, aluminum foil, irregular flat or shaped products, 260... 

The vinyl dispersion industry provides many different products worldwide and uses different processes. When reviewing vinyl dispersions there are basically two types known as plastisol and organosols. These dispersions and examples of processes used will be reviewed. 

Plastisol or paste PVC mixtures are dispersions of emulsion or emulsion/microsuspension PVC resins in plasticisers. Alternatively organosols are based on the use of a lower boiling point liquid. 

Organosol PVC dispersed in an appropriate varnish and conventionally stabilised with a low molecular weight epoxy, resin or epoxidised bean/seed oils Very good Very good Drawn cans Easy-open ends Closures Often used over epoxy-phenolic basecoat... 

This modification [Eq. (6)] of the organoaluminum protecting shell can be used to tailor the dispersion characteristics of the original organosols. A vast spectrum of dissolubilities of the colloidal metals in hydrophobic and hydrophilic media (including water) has been achieved this way. 

Pliovic [Goodyear], TM for homopolymers, vinyl dispersion resin, plastisol, and organosol compounds. 

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