Polyurethane paint coatings

Figure 7 shows the Impedance plots as a function of temperature obtained using a specimen having the polyurethane paint coating. The resistance Is of the order of 10 S2 cm and the... 

Compounds based on S—EB—S usually contain polypropylene, which improves solvent resistance and processibiUty and raises upper service temperatures. Compounds intended for use in the automotive industry are able to survive 1000 hours air exposure at temperatures of 125°C with only minor changes in properties (54). Very soft compounds have been developed to replace foam mbber for interior trim parts. In this and similar appHcations, these soft compounds are usually insert molded over polypropylene or metal and then coated with flexible polyurethane paint (55). Other automotive appHcations include products intended for sound deadening, flexible air ducts, and gear shifter boots, as weU as improving the properties of sheet mol ding compounds. 

Where fumes or deposits which act as anti-oxidants are present, no orthodox paint which dries by oxidation can give satisfactory service. Instead, a coating which dries either by evaporation (e.g. a selected chlorinated rubber paint), or by a cross-linking reaction (e.g. a catalysed epoxy or two-component polyurethane paint) must be used. 

From the data obtained for the different specimens it can be seen that there is significantly different behaviour between the poor, porous coatings (bitumen) and the polyurethane paint samples. Of the polyurethane samples only one showed any evidence of corrosion beneath the coating during the duration of the test and this was an unpigmented single coat specimen. 

Table II shows the details of preparation for the second set of 10 painted steel specimens. A polyurethane paint (Marlnox SR-2, Mabraco International, 20 des Navlgateurs, QuSbec, Canada) along with an initial coating of an aluminxim containing paint (prSpolymSre d aluminium, Mabraco International) was the second type of paint system used in this study.

When a thick coating (-100-160 ijm) of polyurethane paint Is applied (e.g. specimen 29), the activation energy Is of the order of 26 kcal/mol. This Indicates the higher energy barrier presented by a non-porous coating. 

Table III(B). Outdoor and laboratory tests of paint coatings applied over ASa 3 and BSt 2 steel panels. Paint system Polyurethane.

Uses. Polyurethane paints and varnishes as an elastomer in casting compounds, flexible textile coatings... 

Uses. Production of polyurethane foams and plastics used in polyurethane paints and wire coatings the most commonly used material is a mixture of 80% 2,4 isomer and 20% 2,6 isomers... 

Two-pack polyurethane paints exhibit film properties comparable to those of solvent-borne polyurethane coatings (Bittner and Epple, 1996 Mirgel, 1993). 

Abstract— The use of organosilanes as adhesion promoters for surface coatings, adhesives and syntactic foams is described and reviewed in the light of published work. Data are presented on the beneficial effect of silanes, when used as pretreatment primers and additives, on the bond strength of two pack epoxide and polyurethane paints applied to aluminium and mild steel. It is shown that silanes when used as additives to structural epoxide and polyurethane adhesives are less effective than when used as pretreatment primers on metals but are highly effective on glass substrates. The compressive properties of glass microballoon/epoxide syntactic foams are shown to be markedly improved by the addition of silanes. 

Hexamethylene diisocyanate (HDI) is used in the preparation of dental materials, medical adsorbents, and contact lenses, and is used as a polymerizing agent in polyurethane paints and coatings. 

Polyurethanes are also used to make paints, available as water-thinnable paints and powder coatings. Items painted with PU paints benefit not only from a lacquer film, but also from an improved chemical resistance. Polyurethane paints are scratch, abrasion, and impact resistant, and they adhere well to a variety of surfaces. Polyurethane adhesives are similarly good choices as they resist heat, water, solvents, grease, and oils. ... 

The (physically wetting) polyaniline primer CORRPASSIV was compared with a fast-drying two-component epoxy resin primer (Messrs. Finalin, Type 144) and a metal-reactive two-component primer with adhesion-promoting properties (Type 918). All three primers were coated with a two-component polyurethane paint (B412). CORRPASSIV, both with and without top coat, exhibited no rust formation beneath the primer. The slight undermining receded after the test, and even within the cross and scratch injuries, it was virtually impossible to detect any corrosion. 

Isophorone diisocyanate (IPDI) is used in the prodnction of high-qnality coatings, polyurethane paints, and varnishes and as an elastomer for casting componnds. 

The medium-viscosity nitrocelluloses have the broadest application range, a major field being furniture lacquers. They are also employed in paper and metal coatings as well as in reaction lacquers (e.g., acid-catalyzed lacquers and polyurethane paints). 

OH branched, low molecular mass, hydroxy-functional 1000- 5000 melamine resins, free/blocked polyisocyanate resins automotive/ industrial paints, polyurethane/ powder coatings... 

Polyurethane systems based on hydroxypolyester resins and free polyisocyanate resins (two-pack polyurethane paints. Section 2.9) are used particularly for finishes of road vehicles, railroad vehicles, aircraft, and plastics. Blocked polyisocyanate resins are available for formulating one-pack stoving enamels which are particularly suitable for coil and can coatings [2.83]. 

Polyester-polyurethane paints are particularly suitable for coating plastics (maximum drying temperature generally 80 °C) on account of their very high flexibility and good adhesion. 

Depending on their chemical composition, polyurethane paints are formulated as two-component (two-pack) or one-component (one-pack) mixtures. They are applied from the liquid phase, which may be solvent-containing, aqueous, or solvent-free, or from the solid phase as a powder coating. They may be cured under a wide range of conditions drying above to stoving at ca. 200°C. 

Although two-pack epoxy primers and polyurethane intermediate coats have high solids contents, they still contain significant amounts (20-30 wt%) of organic solvents. In polyurethane topcoats, the VOC is even higher. Anticorrosive, waterborne primers based on aqueous dispersions of two-pack epoxy resins and one-pack acrylic resins have been developed to decrease solvent emission. Waterborne, one-pack acrylic topcoats are also used. All of these waterborne paints contain 2 - 5 % organic cosolvents that are required for film formation. 

Details A liquid, used in polyurethane paints, casting compounds and coatings. 

Polyurethane paint High-surface-energy coating 43 mJ/m2... 

Uses Defoamer for water-based systems Ind. polyurethane, acrylate/ polyurethane paints, wood varnishes, furniture paints, pigmented dispersion paints, plastic coatings, inks Properties Colorless to yel. liq. ether-like odor sp.gr. 1.01 g/cc dens. 8.40 Ib/gal flash pt. (Seta) > 100 C ret. index 1.448 > 96% NV Toxicology TSCA fisted... 

Chem. Descrip. Polysiloxane mixt. in dipropylene glycol methyl ether Uses Defoamer for water-based systems ind. polyurethane, acrylate/ polyurethane paints, wood varnishes, furniture varnishes, plastic coatings... 

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