Chlorinated rubber, paint coatings

Figure 1 indicates a typical nitroglycerin facility "inside out" wood frame construction at a concrete floor slab. Note that the exterior cant strip, the lead conductive floor cant and the wood cap are all sloped to discourage product build-up and facilitate cleaning. This assembly also indicates spray-on foam insulation as an optional construction item. At Radford AAP this is a safety approved insulation system. The insulation at Radford AAP received a chlorinated rubber paint coating for weathering. 

Figure 10.27 Blisters in a chlorinated rubber paint coating. (Photo T.G. Eggen, SINTEF Corrosion Centre.)...

For special applications, however, such as for normally humid areas, and contaminated or chemically aggressive locutions, epoxy paints tne con.sidered to be more appropriate. They provide a protective coating which is resistant to chemical fumes, corrosion and temperature. Chlorinated rubber paints, which also fall into the same category of protective paints, may also be used for these areas but, not being temperature resistant, are not preferred to epoxy paints. 

Chlorinated rubber paints and vinyl paints have excellent resistance to high concentrations of acids and alkalis at temperatures up to 80°C. High-build chlorinated rubber paints, which give a thickness of 0.12 mm per coat are commonly used for process plant equipment. 

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. 

A wide range of paints and other organic coatings is used for the protection of mild steel structures. Paints are used mainly for protection from atmospheric corrosion. Special chemically resistant paints have been developed for use on chemical process equipment. Chlorinated rubber paints and epoxy-based paints are used. In the application of paints and other coatings, good surface preparation is essential to ensure good adhesion of the paint film or coating. 

Other uses for alkyds are in general industrial coatings such as machinery and metal furniture. Alkyd resin-chlorinated rubber based coatings are used in traffic paints, but use is declining because of VOC concerns. Some alkyds are still used in refinish paints for automobiles. Uralkyds are used as a vehicle for urethane varnishes for the do-it-yourself market. 

Application. Chlorinated rubber paints can be applied with all conventional coating equipment. The suppliers (manufacturers ) instructions must, however, be observed since the coating material (chlorinated rubber paint) is specifically formulated for the recommended application equipment. 

Uses. On account of their high water resistance, chlorinated rubber paints are used for underwater coatings on steel and concrete (e.g., water storage vessels, swimming pools, sewage systems, harbor installations, and docks). The chemical resistance is... 

The main area of use of chlorinated rubber paints is for underwater coatings on ships (see also Section 11.4). Favorable properties for this application are high water resistance, rapid drying (which is independent of the external temperature in the shipyard), good mutual adhesion of the individual layers, and the fact that old coats of paint can easily be renewed. 

Chlorinated Rubber-Acrylic Resin Combinations. Physically drying acrylic resins are used for these combinations. These combinations have the same drying rates as normal chlorinated rubber paints (see Section 2.3.2). They have improved flow properties (particularly when applied by pouring techniques), improved weather resistance (chalking and yellowing), and favorable mechanical properties (adhesion and extensibility). Applications include topcoats for ship superstructures and priming coats on galvanized surfaces. 

Diisopropyl ketone [565-50-0] (DIPK, 2,4-dimethyl-3-pentanone) is a high-boiling solvent used in the production of cellulose nitrate emulsion lacquers for coating leather, chlorinated rubber paints, and diluents for poly(vinyl chloride) organosols [14.267]. 

Uses Detoamer tor polar org. coating systems, esp. two-part polyurethane paints and furniture finishes, aciyilc paints, chlorinated rubber paints... 

Features Shortens setting time prevents streaking during painting and spraying of chlorinated rubber and coatings prevents chilling of nitrocellulose lacquers... 

Paint 18 Chlorinated Rubber Intermediate Coat Paint... 

General paint coating systems are a combination of oil-type rust preventative primer and long oil alkyd resin paint or chlorinated rubber paint (intermediate and overcoats) with a total thickness of less than 150 p,m. These are applied in relatively mild atmospheres such as rural, mountain, and city. 

Epoxy resin paints, inferior to chlorinated rubber for resistance to strong acids, are excellent for dilute acids and strong alkalis. They produce a harder, more abrasion-resistant coating than does chlorinated rubber and are much better for resistance to fats, oils and many organic solvents. Table 3.50 gives data on the chemical resistance of epoxy resin coatings to different materials. 

Chlorinated rubber floor paints are probably the most common of the lower-cost floor paints on the market. They produce tough and chemically resistant coatings, but their adhesion to concrete is not always good. They tend to wear off in patches and cannot be considered as a durable floor treatment except under light traffic conditions. However, re-coating is a simple job and floors can easily be repainted over weekend shutdowns, for example. Similar paints based on other resins such as acrylics, vinyls and styrene butadiene are also used. 

Thin coatings These pigmented materials, commonly known as floor paints, are often based on chlorinated rubber (see Section 12.3.2) or epoxy ester (see Section 12.3.1). They have limited life in heavy traffic but are easy to apply. 

Chlorinated rubber is soluble in aromatic solvents, and paints made from it dry by solvent evaporation alone. In contrast to the vinyls, there is less difficulty in formulating systems that are suitable for brush application. It has excellent resistance to a wide range of chemicals and to water, but as it is extremely brittle it needs to be plasticised. To preserve chemical resistance it is necessary to use inert plasticisers such as chlorinated paraffin wax. Due to the presence of ozone depleting solvents, chlorinated rubber coatings are being phased out and largely replaced by vinyl acrylic coatings which have very similar performance and can be formulated from lower aromatic or aliphatic solvents. 

Oil-base (including oil-modified alkyd resin) paint films should not be used in alkaline environments as the paint will deteriorate owing to saponification alkali-resistant coatings are provided by some cellulose ethers, e.g. ethyl cellulose, certain polyurethane, chlorinated rubber, epoxy, p.v.c./ p.v.a. copolymer, or acrylic-resin-based paints. In particular, aluminium and its alloys should be protected by alkali-resistant coatings owing to the detrimental effects of alkali on these metals. 

Substrates, Paints and Coatings. Both flash rusting and underfilm darkening studies exployed a white, pH 4.5, primer formulation (see Appendix), designated as Standard, based upon Haloflex 202, a chlorine-containing vinyl acrylic latex. A zinc phosphate free formulation, designated as Non-Standard, of pH6 was prepared by substitution of zinc phosphate for barytes. The comparison paints were a commercial butyl acrylate-methyl methacrylate water borne primer, formulated at pH 9, and a solvent based chlorinated rubber primer. 

To study the effect of contaminants (chlorides and sulphates) at the interface metal/coating, a set of panels (surface A Sa 3) was prepared and dosed with solutions of NaCl and FeSO in distilled water and methanol. Subsequently, two paint systems (chlorinated rubber and polyurethane) were applied on these contaminated surfaces. 

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