关键词: 微纳结构, 多尺度, 静电纺丝, ZnO

Abstract: With the continuous advancement of science and technology and the continuous improvement of people's living standards, product differentiation is the general trend of market development, and people's demand for functional fibers and fabrics has greatly increased. At present, electrospinning technology has been greatly developed, and the process parameters are easy to control. The preparation of electrospun hydrophilic and hydrophobic micro-nanofibers continues to become increasingly mature. The hydrothermally grown zinc oxide (ZnO) has excellent performance, low preparation cost and can be used for large-scale preparation, and the morphology of the grown ZnO can be regulated. By combining electrospinning technology and hydrothermal growth method, a unique micro-nano structure is constructed on the polyacrylonitrile (PAN)-based composite fibers, which is expected to improve the hydrophilicity of the fibers.
To construct multi-scale hydrophilic PAN/ZnO fibers, firstly, the electrospinning technology was used to maintain the mass ratio of PAN to zinc acetate (Zn(AC)2) in the spinning solution at 6:1, the spinning voltage at 20 kV, and the spinning distance at 15 cm. The PAN/Zn(AC)2 composite fibers with uniform and smooth diameter distribution were prepared. Then, the fibers were heat-treated, and different morphologies of sub-micron ZnO structures were vertically grown on the fibers by low-temperature hydrothermal reaction, so that the morphologies of ZnO was diversified and greatly different from the fiber diameter, forming multi-scale PAN/ZnO fibers with excellent hydrophilicity. X-ray diffractometer (XRD), Fourier transform infrared spectrometer(FTIR) and JY-82B video contact angle measuring equipment were used to analyze and test the crystal structure, surface functional groups and water contact angle of the fiber membrane, respectively. The results show that the multi-scale PAN/ZnO fibers can exhibit excellent hydrophilic properties as long as they can grow vertically and evenly on the surface of the fiber to increase the fiber surface roughness, no matter whether the hydrothermally grown ZnO is hexagonal prism, flake, or block. The successful preparation of multi-scale hydrophilic fibers shows that the construction of a rough structure conforming to the Wenzel model on the fiber surface has guiding significance for the hydrophilic and hydrophobic functional finishing of fibers and the corresponding fabrics.
The multi-scale structure hydrophilic fiber successfully prepared in this study provides a high guiding role for the preparation of functional fabrics. If it is applied to the functional finishing of fabrics, it is expected to have broad market prospects.

Key words: micro-nano structure, multi-scale, electrospinnig, ZnO