Tailoring Supramolecular Nanofibers for Air Filtration Applications

Abstract

The demand of new materials and processes for nanofiber fabrication to enhance the performance of air filters is steadily increasing. Typical approaches to obtain nanofibers are based on top-down processes such as melt blowing, centrifugal spinning, and electrospinning of polymer materials. However, fabrication of polymer nanofibers is limited with respect to either a sufficiently high throughput or the smallest achievable fiber diameter. This study reports comprehensively on a fast and simple bottom-up process to prepare supramolecular nanofibers in situ inside viscose/polyester microfiber nonwovens. Here, selected small molecules of the materials class of 1,3,5-benzenetrisamides are employed. The microfiber-nanofiber composites exhibit a homogeneous nanofiber distribution and morphology throughout the entire nonwoven scaffold. Small changes in molecular structure and processing solvent have a strong influence on the final nanofiber diameter and diameter distribution and, consequently, on the filtration performance. Choosing proper processing conditions, microfiber-nanofiber composites with surprisingly high filtration efficiencies of particulate matter are obtained. In addition, the microfiber-nanofiber composite integrity at elevated temperatures was determined and revealed that the morphology of supramolecular nanofibers is maintained compared to that of the utilized polymer nonwoven.

PTFE Emulsion Foam Coating Finishing of Needled Pre-oxidized PAN/PPS Composite Filters

“…The most important parameters to estimate in filter medium are filtration efficiency and pressure drop [14]. Figure 3 illustrated the filtration performance of composite filters tested.…”

Fabrication of silk fibroin/poly(lactic-co-glycolic acid)/graphene oxide microfiber mat via electrospinning for protective fabric

“…Thanks to the emergence of simple and effective sub-micron fiber fabricating technique -electrospinning [6], the development of electrospun protective textiles has attracted a lot of interest from researchers. Many polymer materials, such as polyimide (PI) [7], polyurethane (PU) [8], polyacrylonitrile (PAN) [9], polyamide-66 (PA-66) [10], and some other polymers have been successfully fabricated as nanofibrous membranes for filtration. However, these polymers are pure synthetic fibers which are difficult to biodegrade after use which can cause the serious environmental problem.…”

Controlling the Aspect Ratio of Supramolecular Fibers by Ultrasonication

“…Owing to the controlled self‐assembly process, robust hierarchically structured nanofibers are formed exhibiting appealing mechanical and thermal stability . In particular, these properties render supramolecular nanofibers based on BTAs promising candidates to be used as material for air filtration applications …”