关键词: 中空SiO2, 复合纤维膜, 静电纺丝, 导热系数, 柔软度

Abstract: In order to explore the influence of the particle size of hollow silica (SiO2) in the thermal insulation filler on the thermal conductivity and softness of the fiber membrane prepared by electrospinning, hollow SiO2 microspheres with different particle sizes were designed and prepared. Polyacrylonitrile (PAN) fiber membranes were filled with hollow SiO2 to prepare hollow SiO2 microspheres/polyacrylonitrile (PAN) composite fiber membranes by uniaxial electrospinning. Scanning electron microscope, transmission electron microscope, thermal constant analyzer and other instruments were used to observe, test and analyze the morphology of hollow SiO2 microspheres, the morphology, thermal conductivity and softness of composite fiber membranes. The results show that the self-made hollow SiO2 microspheres have uniform particle size and regular morphology, and there is good dispersibility in the fibers. Besides, adding a small amount of hollow SiO2 microspheres can significantly improve the thermal insulation performance of the composite fiber membrane. Therefore, reducing the particle size is beneficial to increase the thermal insulation performance of the composite fiber membrane. Compared with the thermal conductivity of the pure polyacrylonitrile fiber membrane of 0.0480 W/(m·K), the thermal conductivity of the composite fiber membrane filled with 130 nm hollow SiO2 microspheres is 0.0359 W/(m·K), which is reduced by 25%. And the hollow SiO2 microspheres have a small particle size, which can make the composite fiber membrane maintain higher flexibility.

Key words: hollow SiO2, composite fiber membrane, electrospinning, thermal conductivity, softness