Soybean- and castor-oil-based thermosetting polymers:: mechanical properties

Maleic anhydride modified soybean- and castor-oil-based monomers, prepared via the malination of the alcoholysis products of the oils with various polyols, such as pentaerythritol, glycerol, and bisphenol A propoxylate, were copolymerized with styrene to give hard rigid plastics. These triglyceride-based polymers exhibited a wide range of properties depending on their chemical structure. They exhibited flexural moduli in the 0.8-2.5 GPa range, flexural strength in the 32-112 MPa range, glass transition temperatures (T-g) ranging from 72 to 152 degrees C, and surface hardness values in the 77-90 D range. The polymers prepared from castor oil exhibited significantly improved modulus, strength, and T-g values when compared with soybean-oil-based polymers. These novel castor and soybean-oil-based polymers show comparable properties to those of the high-performance unsaturated polyester (UP) resins and show promise as an alternative to replace these petroleum-based materials. (c) 2006 Wiley Periodicals, Inc.