liquid crystal fibers for temperature sensing
Wearable technology is a rapidly transforming economic market. The increased awareness of personal daily activity and health have opened up a new area of research into functional soft, lightweight materials in order to create these smart wearable devices. Smart fabrics have the potential to comprise clothing and wearable sensors that could be used for camouflage, temperature sensing and physiologic status reporting for health care professionals.
VCU Researchers and U.S. Army collaborators have developed a novel coaxially electrospun thermochromic fiber with high sensitivity to ambient environmental temperature fluctuations. The reflective liquid crystal phase is surrounded by an exterior protective and flexible polyvinylpyrrolidone (PVP). This liquid crystal mixture possesses specific tunable optical properties dependent upon the proportions of the combined liquid crystals. Importantly, these proof-of-concept studies have demonstrated that this manufacturing method by coaxially electrospinning preserves the thermochromic properties of the liquid crystal formulation, while alternative methods may not.
Figure 1. Polarized light microscopy of coaxially electrospun PVP shell, liquid crystal core fibers heated from ambient conditions. As the temperature increases there is a transition from red to blue reflected light that is reversible upon cooling.