Facile supramolecular processing of recyclable adaptive polymer composites for highly reproducible sensory materials

Abstract

Dynamic polymer networks (DPNs), when cross-linked, can display chemical and physical adaptiveness due to their dynamic connections and associated phase transitions. However, the reliable preparation of these conductive composites and achieving consistent performance through recycling remain challenging, primarily due to a lack of systematic approaches. Herein, we describe synergistic association of supramolecular gel and high density dynamic crosslinking using vinylogous urethane (VU) bond that enable highly reliable sensitivity and reproducibility after recycling to high performance adaptive dynamic polymer networks containing conductive fillers. We introduce a straightforward method to create DPNs-single-walled carbon nanotube (SWCNT) composites. This involves facile grinding a random copolymer in a supramolecular eutectic liquid, resulting in a supramolecular gel. Subsequently, dynamic cross-linking is applied. The resulting dynamic polymer-SWCNT (DPC) composites, incorporating a supramolecular gel, demonstrate adjustable electrical conductivity and high sensitivities to various mechanical motions and irradiations, including specific light and heat. Significantly, the DPC exhibits excellent recyclability, along with enhanced reproducibility and sensitivity as a strain sensor compared to other recyclable sensors. Furthermore, we establish a strong correlation between the sensitivity and stiffness of the DPC composite with dynamic cross-linking density. These findings highlight the promising potential of adaptive gel-based processing of DPNs for highly sensitive, recyclable sensory materials with excellent reproducibility. © 2024 Elsevier B.V.