Multiwalled Hollow Polyurethane and Graphene Oxide/Polyurethane Fibers in Janus Textiles for Thermal Management and Sensors
Yanli Ma, Dongming Xing, Mingwei Tian, Lijun Qu, Xueji Zhang, X. N. Hu
Abstract
Multifunctional fibers and wearable textiles have enabled extensive and profound breakthroughs in personal thermal management. In addition to steady-state heat exchange, the initial unsteady-state period plays an integral part in the thermal comfort of humans . Herein, two structure-tunable fibers with inverse thermal properties under unsteady-state conditions were prepared via microfluidic spinning. The multiwalled hollow polyurethane fiber inspired by rabbit hair exhibits good thermal insulation, low thermal absorptivity, and a warm feeling of contact. While graphene oxide nanosheet/polyurethane hybrid fibers possess high thermal absorptivity and an intrinsic cold feeling of contact. As a proof of concept, these two fibers were knitted into different sides as 2D Janus textiles for reversible warm/cool feeling of contact under ambient temperature. Furthermore, compressible 3D smart textiles with a pressure sensor array is also prepared targeting smart insoles and bedsheets, where graphene-modified conductive fiber served as sensor units together with a warm/cool fiber for contact thermal comfort. Such bioinspired structure-tunable fibers focus on the unsteady-state thermal comfort and different contact surfaces can be chosen for summer and winter.