Unsaturated Polyester Resins Are Widely Being Used In Range Of Applications Such As Coating Materials, General Purpose Resins and More

 

Unsaturated Polyester Resins 

Unsaturated Polyester Resins (UPR) are a family of linear polymers that contain double bonds in their backbone. They are prepared by the condensation reaction between dicarboxylic acids and polyhydric alcohols. These resins are widely used in various industries such as sheet molding compound, bulk molding compound, toners and laser printers.

Unsaturated polyester resins can be produced from a variety of starting materials, such as phthalic anhydride, isophthalic acid, terephthalic acid and maleic anhydride. These starting materials can be dissolved in suitable reactive diluents such as styrene. These diluents are then heated and reacted with the unsaturated polyester resin to produce the desired final product.

The use of unsaturated polyester resins is increasing in various end-use industries such as marine, electrical appliances and pipes & tanks. They have a high flexibility, lightweight properties, and resistance against corrosion. These resins can be incorporated into various composites and nanocomposites to enhance their performance. They also provide better material properties such as toughness, stiffness and elasticity.

Besides this, these resins are compatible and readily soluble in reactive diluents and they have good curing properties. This makes them ideal for producing polyester derived products with superior surface quality, thermocycling and UV resistance and clarity.

They are useful for a wide range of applications such as general purpose resins, coating materials, reinforcing materials and as base resins for demanding marine applications. They are particularly well suited to panel, laminates, fiber glass reinforced products, artificial marble, artificial onyx, sheet molding compounds and resin transfer molding applications, as well as for sanitary applications.

A variety of other products such as epoxy, polyurethane, phenolic and acrylic based gelcoats can be made from these unsaturated polyester resins. They have excellent hydrolytic stability and low molecular weights of about 300 to 2500. These polymers have a lower styrene emission and can be modified with different acrylic monomers such as methyl methacrylate, butyl methacrylate and acrylonitrile. This modification increases their versatility and reduces the styrene emission. In October 2020, AOC, Kaprain and Spolchemie announced agreement on AOC acquiring the unsaturated polyester resin manufacturing operations at the Usti nad Labem, Czech Republic site of Spolchemie.