Design of high-performance resin by tuning cross-linked network topology to improve CF/bismaleimide composite compressive properties

Abstract

One effective method for addressing the imbalance between the compression-to-tensile strength ratio in carbon fiber reinforced polymer (CFRP) composites is to create a high-performance resin matrix. We have introduced a bottom-up reinforcement strategy for CFRP composites that involves modifying the bismaleimide resin matrix through the design of its molecular structure. This research utilized the Wittig olefination reaction to convert the polar carbonyl on the bismaleimide monomer to allyl, which resulted in a change in the cross-linked network topology of the bismaleimide resin matrix, and achieved a significant increase in mechanical properties. The tensile modulus of the modified bismaleimide resin matrix reached 5.59 GPa and the mechanism behind this enhancement is discussed in detail. This work is particularly significant due to the preparation and performance evaluation of CF/bismaleimide composites. The compressive strength and interlaminar shear strength of CF/bismaleimide composites showed noticeable improvements of 30.08% and 22.23% respectively, indicating that increasing the modulus of the resin matrix is an effective strategy for enhancing the compressive and interfacial properties of the composite material. Our work aims to offer research insights and design ideas for future exploration of bismaleimide resins in advanced composite resin matrices.