A Multiple Remotely Controlled Platform from Recyclable Polyurethane Composite Network with Shape‐Memory Effect and Self‐Healing Ability

Abstract

Stimuli‐responsive materials can transform from temporary to permanent shapes by specific external triggers. However, the damage might inevitably occur to them when exposed to complex environments, causing a significant reduction in their lifetime and quality. In this study, recyclable remotely controlled shape‐changing polyurethane composite with self‐healing compacity is developed from polyethylene glycol, polytetrahydrofuran diol using isophorone diisocyanate as crosslinker. After the incorporation of magnetite nanoparticles (MNPs), remote heating could be generated by near‐infrared irradiation and alternating magnetic fields. The results show that MNPs are uniformly distributed in the smart networks, resulting in tunable temperature changes of the polymer composite material under various direct/indirect triggering in bending experiments, presenting different shape recovery rates. Moreover, to enhance the self‐healing capability, a disulfide bond is introduced into the polymer networks, and the results show that highly efficient and rapid healing could be achieved from tensile tests, scanning electron microscopy as well as optical microscopy. Additionally, the synergistic effect of transesterification and the dynamic exchange of disulfide bonds brin the networks reproducibility for recycling use. The obtained material is promising to be an alternative material for soft robots and smart sensors.

Bio‐Based and Recyclable Self‐Healing Elastomer for the Application of Self‐Powered Triboelectric Nanogenerator in Low‐Temperature

“…The incorporation of dynamic non-covalent bonds, such as Hbonds, [42][43][44][45] metal-ligand building, [46] host-guest interactions, [47] along with dynamic covalent bonds like 𝛽-hydroxyl lipids, [48,49] disulfide bonds, [50] and imine bonds [51] into bio-based elastomers provides an efficient way to fabricate bio-based elastomers with self-healing and reprocessable properties. These dynamic bonds utilize dissociation and association mechanisms to realize self-healing of elastomers, thereby improving functional reliability and damage tolerance of elastomer materials.…”

Colorless, transparent, and shape memory polyurethane networks with high strength and recyclability

“…Furthermore, the limitations of molding and demolding processes hinder the attainment of complex shapes for thermoset PUs and make post-molding reshaping challenging. To solve the recycling and reprocessing issues of thermoset PUs, the incorporation of dynamic chemical bonds, such as disulfide, 26,27 thiourethane bond, [28][29][30][31] Diels-Alder adduct, [32][33][34] boronate ester bond, [35][36][37] oxime-carbamate bond 38,39 and others, into the cross-linked PU network is typically required.…”