Multi-stimuli temperature, reusable, recyclable, and healable shape-memory epoxy–PEG multifunctional films by regulating polyethylene glycol

Abstract

This study developed a multi-stimuli temperature shape-memory epoxy–polyethylene glycol (PEG) film with skin-responsive and self-healing properties. The epoxy–PEG films can be regulated between rigid and flexible by the dispersion of PEG with different contents. All have excellent shape-memory properties at the respective stimuli temperatures with recovery rates between 92.6 % and 99.0 %. The epoxy–PEG films can perform shape-memory response and healing at room and human body temperatures based on the PEG regulation. The completely cut films with a PEG content of 30 wt% can maintain an average tensile strength of 63.1 % after healing at room temperature. Films with a PEG content of 40 wt% after healing at room and human body temperatures can maintain average tensile strengths of 70.0 % and 93.3 %, respectively. The films healed at human body temperature still maintained an average recovery rate of 85.0 % in the shape-memory cycling test. The environmentally developed shape-memory epoxy–PEG film with controllable thermal and mechanical properties can meet the needs of various stimuli temperatures and execution modes, switching between multiple shapes, self-healing, reuse, reprocessing, and recycling, significantly expanding the application potential for thermoplastic epoxy, especially in the fields of flexible smart materials.