High sensitive, stretchable and weavable fiber-based PVA/WPU/MXene materials prepared by wet spinning for strain sensors

With the advent of an ageing society, wearable strain sensors have great prospects for applications in artificial intelligence, motion detection and healthcare, and have attracted much attention from researchers. But the challenges of poor wear comfort, low sensitivity and clumsy appearance still greatly limited their practical applications. To address these problems, a facile strategy for the fabrication of fibrous strain sensors by wet spinning is proposed. Polyvinyl alcohol/waterborne polyurethane/MXene (PVA/WPU/MXene) is the main component to construct the conductive part of the fiber-based materials and aqueous calcium chloride solution is used as a coagulation bath in the spinning process. The relevant physicochemical properties of the resulting conductive fibers were characterized and tested. Though the facile wet-spinning process, an effective conductive network was achieved in the prepared stretchable sensor with excellent mechanical properties and chemical stability and can be woven into various fabric forms according to practical demanding. It was demonstrated that a sensitivity of 5.61 could be obtained with an elongation at break of over 358%. In addition, the sensing and weaving properties of the composite fibers were characterized, and application performance was measured by placing them on the elbow, wrist, and knee. As a result, the PVA/WPU/MXene composite fiber strain sensor displays a linear response, good sensitivity and cyclic stability and has great potential for wearable strain sensors and flexible strain sensors in complex environments