Preparation of multifunctional PVDF/AgNWs nanofiber membranes and study on their warmth retention properties

Heat insulation and solar energy use are attractive strategies to cope with the serious and external cold environment. Here, silver nanowires (AgNWs) with high purity and aspect ratio were synthesized by polyol method and PVDF/AgNWs nanofiber membranes were prepared by electrostatic spinning. We investigated the warmth retention properties of nanofiber membranes using a heating table and simulated sunlight as the heat source, respectively. The results showed that the nanofiber membrane doped with 2 wt % AgNWs had a high porosity of 84% and thus a low thermal conductivity of 18 mW m −1  K −1 . Meanwhile the nanofiber membrane exhibited stable and long-lasting heat insulation behaviors and the surface temperature of the fiber membrane could reach nearly 43 °C after 5 min of irradiation with a 100 mW cm −2 light intensity and about 70 °C after 2 min of irradiation with a 300 mW cm −2 light intensity. In addition, the nanofiber membrane showed hydrophobicity with a water contact angle of 138° and breathability with air permeability of 75 mm s −1 . The stress and strain of the nanofiber membrane was 3.6 Mpa and 211.3% respectively.