Eugenol‐Derived Bismaleimide High Performance Resins and Composites Using Diisocyanate as Property Modifier

Abstract

AbstractA new kind of high performance bismaleimide resin with good processability and improved toughness is synthesized by chemical modification of 4,4′‐bismaleimidodiphenylmethane (BMI) by eugenol (EG) and different contents of 4,4′‐diphenylmethane diisocyanate (MDI). MDI‐EG‐BMI resins exhibit good thermal stability for its 5% weight loss temperatures around 300 °C and its residue of 41.61% at 900 °C, which are much higher than those of EG‐BMI resin. Then, the carbon fiber‐reinforced MDI‐EG‐BMI composites are fabricated. The mechanical properties of the composites matrixed by MDI‐EG‐BMI resins are better than those by EG‐BMI resin. For carbon/MDI‐EG‐BMI composites, their glass transition temperatures are higher than 300 °C, and their flexural strength, moduli, and toughness are maintained at a range of 217.47–404.36 MPa, 35.12–48.49 GPa, and 1.16–2.63 MJ m−3 respectively; with the contents increasing of MDI in the resin formulation, the flexural properties first increase then decrease; comprehensively the composite with 30 wt% MDI has the best mechanical and thermal properties.