Paint types polyesters

Synthetic resins form the heart of the paint industry. The tw o main types of synthetic resins are condensation polymers and addition polymers. Condensation polymers, formed by condensation of like or unlike molecules into a new, more complex compound, include polyesters, phenolics.. iniino resins, polyurethane, and epoxies. Addition polymers include polyvinyl acetate, polyvinyl chloride, and the acrylates,... 

These requirements are usually met with two-pack paints based on hydroxyl-rich polyester or acrylic resins in the pigmented pack and aliphatic polyisocyanates in the activator pack. Cure with this type of finish is relatively fast and complete even at low ambient temperatures. An alternative finish is an acrylic lacquer, similar to the lacquer used for refinishing motor cars. These finishes are applied to the assembled aircraft by operators protected by air-fed hoods and using airless or conventional spray guns. High durability pigments are included. 

P.R.216 lends color to all types of industrial paints, it is heat stable up to 200°C. Like other pyranthrone pigments, it is suitable for use in unsaturated polyester systems, in which it is resistant to peroxides. 

Another way of producing highly crosslinked polyesters (see Exercise 64) is to use glycerol. Alkyd resins are a polymer of this type. The polymer forms very tough coatings when baked onto a surface and is used in paints for automobiles and large appliances. Draw the structure of the polymer formed from the condensation of... 

There are numerous types of binders currently available to the paint industry for various applications such as alkyds, polyesters, acrylics, vinyls, natural resins, and oils. The more common resins or polymers used in coatings are described in the following subsections ... 

Anisole was also mentioned as a solvent for paints polyimide type (ref. 23), and polyester type (ref. 24) paints or those based on isocyanate (ref. 25). 

Nowadays, amorphous silicon dioxide may be used as corrosion-resistant coatings in various types of cans and as moisture-impermeable films, as well as for rheology control in materials such as paints, silicone rubbers, polyester compounds, dental formulations, emulsions, cosmetics, and excipients in pharmaceuticals. 

MAJOR USES Thinner for paints, lacquers and enamels solvent catalyst for acrylic and polyester type resins gasoline blending raw material for peroxides and oxidation catalysts used in the manufacture of styrene, phenol, acetophenone, polymerization catalysts, alphamethylstyrene, diisopropylbenzene. 

The degree of unsaturation in these oil-modified alkyds was controlled by the amount and type of unsaturated acid used in the formation of the polyester. These unsaturated polymers cured or "dried" through auto-oxldatlon by oxygen from the air which reacted with the unsaturated carbon atoms on the surface of the freshly deposited film. This crosslinking reaction, like that of the "drying" of oil-based paints, was catalyzed by heavy metal salts, such as lead or cobalt salts of organic acids. Alkyds, which are some of the most Important paint resins, are produced at an annual rate in excess of 300 thousand tons. 

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