Alkyd resin, is a complex oil-modified polyester that is widely used in a variety of fields involving paints and coatings industry, woodworking, construction, steel sheets, and adhesives. It has strong mechanical properties and has a good resistance against impact, flex, wear and tear. Depending on the length and its method of polymerization, alkyd resins have various properties: different degrees of film-forming, adhesions, and resistance against external factors.
Alkyd resins can be produced in two stages. In the first stage, vegetable and pentaerythritol are heated with catalyst under the temperature of 270°C for 2 hours. In the second stage, after cooling down to 150°C, phthalic anhydride is added and heated with mixture to 240°C to get polyester alkyd resins. The product is obtained after the removal of water via evaporation.
Alkyd resins are widely used as good binder in the paint industry. It crosslinks with atmospheric oxygen as the solvent evaporates, making the polymer no longer soluble in the original solvent. With this ability, alkyd resins are involved in the formulation of various range of fast-drying media of artists’ paints. They are intended as the main component or one of ancillary components for manufacture of paints or lacquers for general applications. They are used most commonly in products intended for painting of wood and metal.
Metal Casting Industry
Alkyd resins are used in metal casting industry for the creation of sand based molds. These alkyd resins when used for molds are combined with a metallic dryer and a chemical, in the form of a polymeric isocyanate, to enhance drying time. In this setting, the alkyd binds sand-based molds together, drying with no toxic fumes.
Alkyd resins are used in the preparation of encapsulation material for resistor and capacitor. They do not conduct electricity and are heat resistant. They are even used in switches and as insulation for circuit breaker.