Organosol

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. 

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). 

For vinyl plastisol, organosol products and calendering, Day-Glo Color Corp. offers T, D, VC, and AX-Series pigments, Lawter Chemical offers the B-3500 and G-3000 Series, and Radiant Color offers P-1600 and R-203-G Series. In addition, Day-Glo offers VC Series for vinyl calendering where nonformaldehyde products are needed. 

OGORKIEWICZ, R. M. (Ed.), Thermoplostics Effects of Processing, lliffe, London (1969) SARVETNicK, H. A. (Ed.), Plastics and Organosols, Van Nostrand-Reinhold, New York (1972) TADMOR, z., and gogos, c. g.. Principles of Polymer Processing, Wiley, New York (1979)... 

A number of basic paste types may be distinguished. The most important classes are the plastisols, the organosols, plastisols incorporating filler polymers (including the rigisols), plastigels, hot melt compounds, and compounds for producing cellular products. 

Organosols (Mix B, Table 12.5) are characterised by the presence of a volatile organic diluent whose function is solely to reduce the paste viscosity. After application it is necessary to remove the diluent before gelling the paste. Organosols are therefore restricted in use to processes in which the paste is spread into a thin film, such as in the production of leathercloth. Because of the extra processes involved, organosols have not been widely used, in Europe at least. 

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

Organosol Suspension of finely divided resin in a volatile organic slurry. 

As normally polymerized, PVF melts between IH5 and 210 °C and contains 12 18% inverted monomer units ft is normally considered a thermoplastic, but because of its instability above its melting point, it cannot be processed by conventional thermoplastic techniques Instead it is generally extruded into films in a solvent swollen (organosol) form and the solvent is subsequently evaporated and recovered Such films can be onented further to achieve specific mechanical properties PVF films are exceptionally weather and radiabon resistant considenng their modest fluonne content PVF is insoluble below 100 °C but, at higher temperatures, it dissolves in polar solvents like amides, ketones, tetramethylene sulfone, and tetramethylurea Resistance to acids and bases at room temperature IS good [1, 29 ... 

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. 

PVC, PVA, PVAC, Copolymers) organosols forms available including hard and flexible types. Properties are highly dependent on plasticizer used. May be injection, extrusion, compression molded, vacuum formed. Low cost. antistatic sheet and hose, RF gaskets, heat-shrinkable tubing. 

Corrosion has been encountered infrequently to date and has been a surface type, as opposed to pitting corrosion that can result in perforations. Entrapped air in the beverage or in the cans headspace increases the corrosive action of the product according to Koehler et at (21). As with beer and other canned foods, aluminum ends provide electrochemical protection when combined with tinplate or tin-free-steel can bodies. The level of iron pickup is reduced while the amount of aluminum dissolved in soft drinks increases without detrimental effect. Aluminum containers with vinyl epoxy and vinyl organosol coatings are compatible with carbonated soft drinks. 

This is the basis of a generally applicable multigram synthesis routes to isolable 1-10 nm organosols of the transition metals that are easily redispersible in high concentration in organic phases (Figure 7) [3,183]. 

Typically the [NR4] -stabilized raw organosols contain 6-12 wt% metal but for metals such as rhodium they can be converted to pure colloids containing... 

Figure 7. Metal organosols accessible via the NR4(Bet3H) route (Equation (2)). (Reprinted from Ref. [53], 2007, with permission from Wiley-VCH.)...

The catalytic applications of Moiseev s giant cationic palladium clusters have extensively been reviewed by Finke et al. [167], In a recent review chapter we have outlined the potential of surfactant-stabilized nanocolloids in the different fields of catalysis [53]. Our three-step precursor concept for the manufacture of heterogeneous egg-shell - nanocatalysts catalysts based on surfactant-stabilized organosols or hydrosols was developed in the 1990s [173-177] and has been fully elaborated in recent time as a standard procedure for the manufacture of egg-shell - nanometal catalysts, namely for the preparation of high-performance fuel cell catalysts. For details consult the following Refs. [53,181,387]. 

Depending on the nature of these protecting shells, the resulting metal colloid may be taken into organic (organosols) or aqueous (hydrosols) medium. Lipophilic protective agents such as... 

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