Electrospining Machine:Prof. Zhong Zhaoxiang, Nanjing University of Technology, et al: Multifunctional Nanofiber Membrane with Asymmetric Wettability and Pine Needle-like Structure for Enhanced Moisture Transfer and Sweat Transfer

Background

Recently, Prof. Zhong Zhaoxiang's team at Nanjing University of Technology has successfully prepared multi-functional Nanofiber Membrane with asymmetric wettability and pine-needle-like structure for enhanced moisture-absorption and perspiration through hydrothermal treatment after continuous electrostatic spinning.

The related research results are titled “Multi-functional nanofiber membranes with asymmetric wettability and pine-needle-like structure for enhanced moisture-absorption and wicking”. wicking” was published in the journal Chemical Engineering Journal.

The main points of this paper

1. Multifunctional Nanofiber Membrane with asymmetric wettability and pine-needle-like structure was successfully prepared by hydrothermal treatment after continuous electrostatic spinning.

2. Zinc oxide (ZnO) nanorods grown in situ on hydrophilic polyacrylonitrile (PAN) fibers guided water transfer by extending into hydrophobic polyvinylidene fluoride (PVDF) channels, which enhanced unidirectional water transport.

3. At the same time, the ZnO nanorods release antimicrobial active ingredients that increase the contact between the fibers and the aerosol, thereby inactivating harmful microorganisms after the aerosol is captured by the membrane.

4. The PVDF/(ZnO NRs@PAN) membrane has excellent water vapor transport rate (12.47 kg m-2 d-1), PM0.3 removal rate (99.83%) and bacterial inhibition rate (99.99%). After 10 cycles of filtration and cleaning, the membrane still maintained high filtration performance.

5. The membrane has a wide range of applications in scenarios involving aerosol filtration, moisture management and microbial inhibition, such as masks, protective clothing and fresh air systems.

Preparation process of multifunctional Nanofiber Membrane:

In this study, researchers prepared PVDF/(PAN-ZnO) membranes with asymmetric wettability and pine-needle-like structure by growing ZnO nanorods on hydrophilic fibers.

1. Zn(Ac)2 was first introduced into the PAN fibers and converted to ZnO under heat treatment at 130°C.

2. Then, ZnO nanorods were grown in situ in PAN-ZnO fibers of PVDF/(PAN-ZnO) membranes by hydrothermal reaction.

3. Finally, after sufficient washing and drying, PVDF/(ZnO NRs@PAN) membranes with asymmetric wettability and pine-needle-like structure were obtained

How does the asymmetric wettability of Nanofiber Membrane contribute to enhanced wetting?

The asymmetric wettability of Nanofiber Membrane promotes the directional transport of water, which enhances the hygroscopic properties. This was achieved by designing membranes with hydrophobic and hydrophilic regions, allowing unidirectional movement of water. The presence of pine-needle-like zinc oxide nanorods on the hydrophilic fibers further enhances this mechanism of directional water transport, reducing the driving force required for water transport and ultimately increasing the wicking capacity.

Originallink: https://doi.org/10.1016/j.cej.2023.143709