Unsaturated Polyesters

Published July 1967

This report is concerned with the process economics of producing unsaturated polyester resins. Commercial unsaturated polyesters are a family of products based on the esterification of glycols and saturated and unsaturated dicarboxylic acids and anhydrides, and capable of cross-linking with another unsaturated monomer to form thermosetting copolymers without the evolution of volatile by-products. The final cured products can be formed with or without the application of heat or pressure, enabling the fabricators to use simple and inexpensive equipment to make large and complex objects. The versatility of the formulation for the unsaturated polyester resins permits the manufacturers to produce various grades of many types of resins to suit different fabrication methods and end product requirements. Unsaturated polyester resins are the predominant resinous raw material used in reinforced plastics, which are growing rapidly.

Their uses in nonreinforced areas are also on the increase. The study includes four processes; namely, fusion, solvent, batch epoxide, and continuous epoxide processes. The first two methods are commercial processes using glycols and saturated and unsaturated dicarboxylic acids and anhydrides as starting materials. They are batch processes and are used to produce a large variety of unsaturated polyester resins.

Other PEP Related Reports:

• Unsaturated Polyesters 26A