A Tailorable Series of Elastomeric-To-Rigid, Selfhealable, Shape Memory Bismaleimide

Small. 2024 Apr;20(15):e2307244. doi: 10.1002/smll.202307244. Epub 2023 Nov 23.

Abstract

In recent years, there has been rapid development in the field of shape memory materials with active deformation performance. However, bismaleimide, a widely used thermosetting material in aerospace, has been largely overlooked in shape memory applications. This work presents the synthesis of a molecule containing an alkene bond adjacent to an oxygen atom. Through molecular design, a one-time reaction between this specialized molecule and the bismaleimide molecule is successfully achieved, facilitated by the steric hindrance effect. Therefore, a new series of shape memory bismaleimide materials are obtained. By introducing a diamine to adjust the chain length, the properties of material are further improved, resulting in increasing static modulus by 506 times. The synthesized materials exhibit a broad glass transition temperature (Tg) range exceeding 153 °C, remarkable stiffness tunability. Notably, in the synthesis process of this materials series, the disulfide bonds are introduced, which facilitates the realization of self-healing and reprocessable functionalities in the resulting thermosetting materials. This significant advancement lays a solid foundation for the future recycling and reuse of aircraft, satellites, and other equipment, offering promising prospects for enhancing sustainability and efficiency within the aerospace industry.

Keywords: bismaleimide; reprocessable crosslinked polymers; self‐healing materials; shape memory polymers.