Adipic acid – glutaric anhydride – epoxidised linseed oil biobased thermosets with tunable properties

Abstract In this study, the preparation and characterization of biobased thermosets comprising epoxidized linseed oil (ELO), adipic acid and/or glutaric anhydride, initiated by N , N -4-dimethylaminopyridine (DMAP) is reported. By changing the ratio of adipic acid to glutaric anhydride, the obtained resins changed from soft and flexible to hard and brittle materials. The Young’s modulus varied from 25 MPa to 1477 MPa, tensile strength varied from 10.3 MPa to 25.7 MPa, and the elongation at break varied from 2.7% to 67.5%. The maximum toughness was found with the sample containing 20% glutaric anhydride and 80% adipic acid. With the increase of glutaric anhydride content, the total heat released during the curing reaction and the glass transition temperature ( T g ) increased. This is the first paper that reports the combination of glutaric anhydride and adipic acid as curing agents for epoxidized plant oils to produce thermosets ranging from flexible to hard.