Directional Water Transfer Janus Nanofibrous Porous Membranes for Particulate Matter Filtration and Volatile Organic Compound Adsorption

Abstract

In order to reduce the possible harm caused by air pollution, excellent personal protective materials are attracting more and more attention. Therefore, the research of multifunctional materials that can filter particulate matter (PM) and volatile organic compounds (VOCs) simultaneously is of great significance. In addition, in cold weather, water vapor in the exhaled gas condenses into small droplets inside the respirator causing uncomfortable feeling of dampness. Herein, we prepared several types of cyclodextrincontaining Janus nanofibrous porous membranes by electrospinning, which can efficiently filter PM of different sizes in the air, effectively adsorb VOCs, and orientate moisture from exhaled gas to the outside of the membranes to provide a dry and comfortable environment. These advantageous features, combined with the cheap price and easy availability of component materials and low respiratory resistance, highlight the great potential of these Janus nanofibrous porous membranes in the development of personal wearable air purifiers.

Supramolecular Assembly of β-Cyclodextrin-Modified Polymer by Electrospinning with Sustained Antibacterial Activity

“…The stretching vibration peaks of C–H were at 2943 and 2866 cm –1 ; the bending vibration of C–H were in the 1471–1365 cm –1 region; the peak at 1723 cm –1 was assigned to CO; and the peaks in the 1294–1165 cm –1 region were the characteristic peaks of C–O–C. These above results indicated that PCL nanofibers were successfully constructed . The peak at 3330 cm –1 was assigned to O–H of PVA.…”

“…These above results indicated that PCL nanofibers were successfully constructed. 38 The peak at 3330 cm −1 was assigned to O−H of PVA. The infrared spectra of the four membranes were very similar because the signals of the characteristic peaks of PCL were very strong; thus, the signals of some other functional groups can be easily masked and are difficult to be detected.…”

Electrospun Nanofiber Membranes for Air Filtration: A Review

“…The core–sheath structure and Janus structure studied by researchers are currently mostly multilayer structures from the macroscopic point of view. For instance, the Janus structure prepared by Xu et al [ 200 ] is visible on the front and back sides of the macroscopic view, but the nanofiber membrane does not have a Janus structure on the microstructure level, and this can be understood as a two-layer filter membrane. The advantages of the coaxial electrospinning process and parallel electrospinning process are that two or more polymers are organically unified without increasing the thickness of the fiber film; for example, core–sheath fiber membranes prepared by coaxial electrospinning can be designed with the core layer as the quality layer and the sheath layer as the functional adsorption layer, and Janus fibers prepared by electrospinning in parallel can combine two materials with different characteristics that contact the air at the same time to form a synergistic effect.…”

High-performance multifunctional electrospun fibrous air filter for personal protection: A review

“…During the use of the air filter, the exhaled water vapor may cause uncomfortable feelings: for hydrophobic materials, low water vapor transmission rate will lead to a sense of moisture, while for hydrophilic materials, the moisture will be absorbed to form a liquid film and make the air resistance rise rapidly. The purpose of water vapor transmission system is to achieve efficient directional transmission of water droplet and vapor, thus avoid the rising air resistance and wet–sticky feeling caused by exhaled water vapor to realize comfortable use [164] . Constructing hydrophobic/hydrophilic gradient structure (i.e., Janus membrane) is an effective method to realize directional water droplet or vapor transport, which has been widely used in wound dressing, protective clothing, oil–water separation and so on [165] , [166] , [167] , [168] .…”