Highly conductive and elastic multi-responsive phase change smart fiber and textile

Abstract

Smart fiber, which can sense external environment changes intelligently and response quickly, has become an important building block to weave wearable system. Wet-spinning phase change materials (PCM) into smart fabrics offers great promise to regulate temperature and achieve personized thermal comfort in an intelligent way. However, the intrinsic low mechanical elasticity and stimuli responsiveness of PCM seriously blocking its application in wearable systems. In this work, we developed an ultra-stretchable PCM-based smart fiber for personal healthcare and thermal management, via wet-spinning PCM microcapsules embedded in elastic polyurethanes with dual responsive networks. Organic poly(3,4-ethylene-dioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) “glued” inorganic carbon nanotubes/graphene skeleton into 3D hierarchically interconnected responsive and sensitive network along elastic fibers, which not only exhibits high sensitivity to multi stimuli (mechanical/electrical/thermal/light), but also facilitates efficient carrier transfer between PCM microcapsules for rapid response. Elastic PCM-based smart fiber with high mechanical stretchability (>200%) not only could adapt to the intense large movements seamlessly, but also convert these deformations into electrical signals for healthcare monitoring. Furthermore, the stretchable conductive PCM-based smart fiber(1.96×104 S/m) still remains robust stimuli-responsiveness with excellent Joule heating and photothermal effect even under large mechanical deformations, which could convert multi stimuli into latent thermal energy during response process and store it for self-powered personal thermal management. The robust PCM-based smart fiber with outstanding knotting capability can be woven into large-scale breathable textiles. The stretchable multi-responsive PCM-based fiber holds great potential in emerging wearable electronics and smart textiles.