Nonwoven Membranes with Infrared Light-Controlled Permeability

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Developing smart materials with tunable properties is crucial for advanced applications.
• Nonwoven fiber mats (NWFs) offer a versatile platform for functionalization.
• Controlling membrane permeability remotely is a significant challenge in microfluidics and separation technologies.

Purpose of the Study:

• To develop the first composite NWFs with infrared light-controlled permeability.
• To investigate the "photothermal smart-gating" mechanism using graphene oxide nanoparticles (GONPs) and poly(N-isopropylacrylamide) (PNIPAm)-based microgels.
• To explore the tunability of permeability control by adjusting material design parameters.

Main Methods:

• Coating polypropylene NWFs with PNIPAm-based microgels impregnated with GONPs.
• Utilizing infrared light to induce localized heating via GONPs, triggering microgel contraction.
• Investigating the effect of light dosage and material composition on membrane permeability.
• Comparing the performance of functionalized NWFs with control groups (GONP-free microgels and native NWFs).

Main Results:

• Successful demonstration of infrared light-controlled "photothermal smart-gating" in NWFs.
• Infrared light exposure caused rapid temperature increases, leading to microgel contraction and reduced permeability.
• Permeability control was reversible upon cooling.
• Tuning the monomer composition and GONP-to-microgel ratio allowed for adjustable permeability shifts.
• NWFs with GONP-free microgels showed only thermal responsiveness, while native NWFs lacked smart-gating behavior.

Conclusions:

• The developed composite NWFs offer effective remote control over membrane permeability using infrared light.
• The "photothermal smart-gating" mechanism relies on the synergistic effects of GONPs and PNIPAm microgels.
• This technology holds promise for applications involving temperature-sensitive bioactive ingredients and remote-controlled bioreactors.