Paint types acrylated rubber

Break-in tools used to gain access to premises may well carry traces of paint that have abraded from painted surfaces at the point of entry. Commonly encountered household paint types include polyvinyl acetate (PVA), acrylics, alkyd enamels, epoxies, and chlorinated rubbers. Py-GC can distinguish between these different classes (Figure 8.4). 

There are numerous types of paint employed in the protection of steel and they are designed to meet the conditions imposed by the environment in which they are expected to function. For steel exposed to the atmosphere, the most common type of paint system is based on alkyl resin and this may be mixed with other types or may itself be chemically modified for a specific purpose, e.g. vinyl toluenated or styrenated to give rapid drying. Other generic types are chlorinated rubber, vinyl, acrylic, epoxy, and polyurethane. All have particular attributes and limitations and selection is usually a matter of discussion between user and supplier. 

FIG U RE 8.4 Pyrograms of vinyl acetate, acrylic, aUcyd enamel, epoxy, and chlorinated rubber type architectnral paints. 1 = benzene, 2 = isooctene, 3 = acetic acid, 4 = 2-ethylhexyl acrylate, 5 = 2,2,4-trimethyl 1,3-pentanediol mono-isobutyrate, 6 = methyl methacrylate, 7 = butyl methacrylate, 8 = acrolein, 9 = methacrolein, 10 = hexanal, 11 = phthaUc anhydride, 12 = phenol, 13 = isopropenylphenol, 14 = bisphenol A, 15 = xylenes, 16 = trimethylbenzenes. 

Newer types of high-performance paints used on ship exteriors include those based on epoxy resins, polyurethane resins, vinyl resins (also vinyl/ alkyd or vinyl/acrylic blends) or chlorinated rubber. Epoxies and polyurethanes are chemically-curing types and present curing problems at low temperatures, whilst the overcoating intervals are critical for best adhesion... 

The technique of polymerisation in emulsions provides a good illustration of the condensation-type synthesis. It is also of great importance in industry, where it is used to produce millions of tonnes of latex. Aqueous dispersions of polymers are either destabilised in order to recover the polymer, as in the synthetic rubber industry, or used without transformation, as a binding agent in the paper industry for making coated paper. Latexes are also an essential component of acrylic and vinyl paints, which can be diluted with water and are popular with the general public because of their easy application and absence of odour. 

The synthetic isoparaffins are suitable solvents for alkyd and acrylic paint formulations. These virtually odorless solvents and their low surface tensions offer improved flow and wetting properties to the paints. The excellent wetting characteristics of these solvents are desirable in formulations such as furniture polishes, car polishes, and waterless hand cleaners. The low surface tension of these solvents reduces the amount of surfactants needed in emulsified products and affords improved wetting of pigments in ink and coating formulations. The isoparaffins are used as an inert process solvent in the manufacture of polyolefins and certain rubbers. In the slurry polymerization process the isoparaffins afford solvency for the Ziegler-type catalyst and the ethylene monomer, but no solvency for the polyolefin polymer product. 

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