Polyvinyl acetate coating

Figure 54 LEIS admittance map of two scribe marks on 10 (im thick polyvinyl chloride/ polyvinyl acetate coating on A1 alloy 5182 (Al-2.5 Mg) after exposure to 3.5 wt% NaCl for 24 h. The map was collected using a 15 mV amplitude voltage perturbation at 500 Hz. Underfilm corrosion is occurring in association with the rightmost scribe, as indicated by the extended high admittance region located approximately at x = 2, y = 1. (From M. W. Wittmann, R. B. Leggat, S. R. Taylor. J. Electrochem. Soc. 146, 4071 (1999).)...

Polyvinate. [Rowe Ftods. Distributiai] Polyvinyl acetate coating. 

Polyvinyl alcohol By hydrolyzing of polyvinyl acetate Coating agent. Lubricant... 

The particles of polyvinyl acetate coated with partially hydrolyzed polyvinyl alcohol cannot form a very tightly coalesced film. This is because polyvinyl alcohol has a higher than, and is not compatible with, polyvinyl acetate. As a result, the dried film will have a hazy, flat appearance. This contrasts with a surfactant-protected acetate, which will coalesce more tightly and will therefore form a clear, glossy film. The dried film of a surfactant-protected emulsion will be much less water sensitive than that of a polyvinyl alcohol-protected emulsion. This is attributable to the water solubility of polyvinyl alcohol, and can be overcome to various degrees by crosslinking of the PVOH after film formation has occurred. 

A bond coat of a polymer latex (also called polymer emulsions or dispersions) such as styrene butadiene (SBR), polyvinyl acetate (PVA) acrylics or modified acrylics. These are applied to the prepared concrete as... 

Polyvinyl acetate and derivatives Polyvinyl acetate is used largely for coating applications, but the derivative polyvinyl alcohol, will, providing there are some residual acetate groups, dissolve in water. Reaction products of polyvinyl alcohol with aldehydes such as polyvinyl formal and polyvinyl butyral are highly specialised materials. 

Uses Preparation of sodium and butyl benzoates, benzoyl chloride, phenol, caprolactum, and esters for perfume and flavor industry plasticizers manufacture of alkyl resins preservative for food, fats, and fatty oils seasoning tobacco dentifrices standard in analytical chemistry antifungal agent synthetic resins and coatings pharmaceutical and cosmetic preparations plasticizer manufacturing (to modify resins such as polyvinyl chloride, polyvinyl acetate, phenol-formaldehyde). 

Uses Manufacture of polyvinyl acetate, polyvinyl alcohol, polyvinyl chloride-acetate resins used particularly in latex paint paper coatings adhesives textile finishing safety glass interlayers. 

The principal synthetic polymers used as coatings are alkyd resins, styrene copolymers, polyvinyl acetate (PVAc), urea, melamine, phenolic and epoxy... 

RDX/SantowaxM 91/9 RDX/Be Square Special Wax The compns containing the Santowax M (product of Monsanto Chemical Co Santowax M is a meta-diphenyl benzene, a hard microcrystalline wax very stable to heat with a mp of 181-84°F) were found most suitable with respect to ease of manuf and non-adherence to punches and dies. They were more satisfactory than the standard Compn A-3. Both the Santowax M and the Be Square Special Wax coated the RDX crystals well the polyvinyl acetate/dibutylphthalate did not. The PVA/DBP, during the RDX coating... 

For desensitization of solid HE s, the usual procedures are to coat them with one or several of the following paraffin, paraffin oil, waxes, stearic acid, stearates, PVAcet (polyvinyl acetate) DNT, etc. W8hler (Ref 3) detd the maximum percentage of paraffin oil which could be incorporated in a HE without making it detonate incompletely. He named this value Phlegmatizier-ungsgrenze (Phlegmatization Limit), which probably may be called Desensitization Coefficient. These values were found to be 6.75% (of paraffin oil) for TNT, 8.25 to 8.75% for Tetryl and 8.25% for PETN. The procedure was as follows ... 

For the packaging of sensitive foods, PP films are coated with polyvinylidene chloride, polyvinyl acetate, EVAcopolymers, polyacrylates, styrene-butadiene copolymers, LDPE, poly-l-butene or random copolymers of propene with ethylene and 1-butene. By using these various coatings PP has recently sharply reduced the use of regenerated cellulose (cellophane), the previous market leader in this area. 

Many epoxy dispersions are compatible with most types of latex emulsions including acrylic, urethane, styrene butadiene, vinyl chloride, and polyvinyl acetate. The epoxy dispersion can be used as a modifier for these emulsions to alter handling and application characteristics such as emulsion rheology, foaming tendencies, pH sensitivity, wetting properties, and coating coalescence. They can also be reacted into the latex resin either by reacting the epoxy with a functionalized latex or by use of an epoxy with a coreactant. In this way adhesive systems can be formulated that are cured at room or elevated temperatures. 

Fig 1 Scheme of the screen-printed process a typical thick-film screen consists of a finely woven mesh of stainless steel, nylon or polyester, mounted under tension on a metal frame, normally aluminium. The screen defines the pattern of the printed film and also determines the amount of paste which is deposited. The mesh is coated with a ultraviolet sensitive emulsion (usually a polyvinyl acetate or polyvinyl alcohol sensitized with a dichromate solution) onto which the circuit pattern can be formed photographically. The ink is placed at one side of the screen and a squeegee crosses the screen under pressure, thereby bringing it into contact with the substrate and also forcing the ink through the open areas of the mesh. The required circuit pattern is thus left on the substrate... 

Organic solvents are most commonly used, and encapsulating polymers include ethylcellu-lose, NC, polyvinylidene chloride, polystyrene, polycarbonate, polymethylmethacrylate, polyvinyl acetate and others. Interfacial polymerization produces a polymer such as nylon at the interface between layered solns of two precursor materials such as (in the case of a nylon) a diamine and a diacid (Refs 3 11). If the particle or droplet to be encapsulated is made to pass thru the interface by, say, sedimentation, it will pick up a coating of the polymer as it passes thru... 

Plasticizers are often included in polyvinyl acetate phthalate coating formulations to enable a continuous, homogeneous, noncracking film to be produced. Polyvinyl acetate phthalate has been shown to be compatible with several plasticizers such as glyceryl triacetate, triethyl citrate, acetyl triethylcitrate, diethyl phthalate and polyethylene glycol 400. 

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