Nondrying alkyd resins

Nondrying alkyd resins cross-linked with melamine resins at elevated temperature are used for industrial coatings. Resins containing synthetic fatty acids and resins based on glycidyl esters of Versatic Acid (Cardura E 10, Shell) are used in combination with low-viscosity melamine resins such as hexamethoxymethylmelamine. p-Toluenesulfonic acid and its amine salts are used as catalysts. On account of their high storage life, hydrophobic oxime esters of sulfonic acids are also employed. 

Duraplex. Trademark of Rohm Haas Co for drying and nondrying oil-modified alkyd resins derived from phthalic anhydride, poly-hydric alcohols, and vegetable oils (Ref 2). 

Except when nondrying alkyds are used strictly as plasticizers for other thermoplastic polymers, alkyd resins do not remain as a thermoplastic material in their ultimate application. The film integrity is largely derived after the resin molecules have been cross-linked, either through the unsaturation functionalities on their fatty... 

Nitrocellulose-based lacquers often contain a fair amount of short- or medium-oil alkyds to improve flexibility and adhesion. The most commonly used are short-oil nondrying alkyds. Amino resins or urethane resins with residual isocyanate functional groups may be added to cross-link the coating film for improved... 

Duraplex. Trademark of Rohm Haas Co for drying and nondrying oil-modified alkyd resins derived from phthalic anhydride, poly-hydric alcohols, and vegetable oils (Ref 2). It was used by Aerojet Engineering Corp, Azuza, Calif as an ingredient of some solid propellants, such as RL-223 (Ref 1)... 

The oils in alkyd resins are usually of vegetable origin. They are classified by the type and amount of residual unsaturation into drying, semidrying, and nondrying oils. The drying oils contain most residual unsaturation, while the nondrying ones contain mostly saturated fatty acids. 

Both drying and semi-drying oils can be used to make alkyd resins which dry by oxidation. Nondrying oils give alkyds suitable as plasticizers, particularly for nitrocellulose lacquers or stoving amino resin paints. 

The coating industry has met these problems with blends of alkyds and heat-reactive amino resins. With such vehicles, adequate performance can be achieved through baking cycles of 30—40 min at temperatures of 250—300°F. In general, where initial color and color retention are the prime requisites, nondrying alkyds are most widely used. 

Nondrying oil alkyd-amino resin blends give baking enamels with excellent resistance to soap and alkali. A replacement of 25% of the short-oil, nondrying alkyd with a short-oil, drying alkyd will give shghtly better adhesion with a sacrifice in soap and alkali resistance. 

Fatty acids and oils are one category of primary raw materials for alkyd resins. Their chemistry and compositions have been discussed in Section 2.2.3. Soybean oil, linseed oil, tall oil, sunflower oil, and safflower oil are common raw materials for air-drying alkyds, while coconut oil and castor oil are important for nondrying alkyds. 

Chem. Descrip. Glycerol esterified rosin ester CAS 8050-31-5 EINECS/ELINCS 232-482-5 Uses Modifying resin for lacquers, paints, and adhesives Features Multipurpose compat, with nitrocellulose and nondrying/drying short, med., and long oil alkyds... 

From the THM chromatogram it is evident that the paint is a pentaerythritol-orthophthaUc acid baked alkyd enamel having a coconut nondrying oil cross-linked with a butylated melamine formaldehyde resin. 

The products from the above polyesterifications are brittle materials. They are therefore modified with oils, either drying or nondrying. Such oil-modified resins bear the names of alkyds. While glycerol is widely used, other polyhydroxy compounds (polyols) are also utilized. These may be trimethylolpropane, pentaerythritol, sorbitol, or others. Phthalic anhydride is usually used in alkyd preparations. Other dicarboxylic compounds, however, may also be included for modification of properties. Common modifiers might be isophthalic, adipic, or sebacic acids, or maleic anhydride. In addition, many other acid modifiers are described in the patent literature. 

Offset ink chemistry formulations are customized for a wide range of substrates and ink performance requirements relative to each printed and/or coated end product. As detailed in Tables 8.6 to 8.8, oil-based offset inks contain pigments, drying and nondrying (rheology-controlling) oils, waxes, catalysts, and resins. Natural resins are comprised of alkyds, whereas synthetic resins can include phenolics, urethanes, maleics, acrylics, and epoxides. 

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