Alkyd Resin Binders and Uses

DIN 53183 defines an alkyd resin as follows Alkyd resins are synthetic polyester resins produced by esterifying polyhydric alcohols with polybasic carboxylic acids. At least one of the alcohols must be trihydric or higher. Alkyd resins are always modified with natural fatty acids or oils and/or synthetic fatty acids. In order to obtain particular application technology properties, alkyd resins may be additionally modified with compounds such as resin acids, benzoic acid, styrene, vinyltoluene, isocyanates, acrylic, epoxy, or silicone compounds.  

Worldwide alkyd resin production (including captive-use amounts) is estimated to be 2 -3 X 10 t. Detailed information on commercially available alkyd resins can be found in [2.62]. 

The properties of alkyd resins can be widely modified by selecting appropriate vegetable oils and fats/fatty acids, varying their content in the resin, and by using special synthetic acids and a variety of modifying agents. 

Long oil drying alkyd resins are used as binders for architectural and do-it-yourself paints, and are mainly modified with soybean oil. In the absence of direct light, they do not yellow as much as linseed oil alkyd resins and are less expensive than safflower oil types. Long oil linseed oil alkyd resins are principally used in corrosion protection coatings and colored architectural coatings. 

Short oil alkyd resins are used in combination with amino resins for industrial stoving finishes (e.g., for metal furniture, radiators, bicycles, garage doors, and small 

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