Electrospun biodegradable polycaprolactone filter media for filtering facepiece respirators

Area of Science:

• Materials Science
• Environmental Science
• Biomedical Engineering

Background:

• Conventional filtering facepiece respirators (FFRs) utilize meltblown polypropylene, relying on electrostatic charges and are not biodegradable.
• Electrospun filters offer high filtration without electrostatic charging due to small fiber size and can be made from degradable materials.

Purpose of the Study:

• To design and fabricate biodegradable filter media from poly(ε-caprolactone) (PCL) nanofibers.
• To evaluate if these PCL nanofiber filters meet N95 performance standards for filtration efficiency and breathing resistance.
• To demonstrate the fabrication of prototype respirators using these novel filter materials.

Main Methods:

• Electrospinning of biodegradable poly(ε-caprolactone) (PCL) nanofibers from a benign solvent system.
• Characterization of filter media, including average fiber diameter, solidity, and basis weight.
• Laboratory testing of filter media and prototype respirators for filtration efficiency and inhalation/exhalation resistance.

Main Results:

• Biodegradable PCL nanofiber filter media were successfully fabricated with fiber diameters ranging from 60 nm to 300 nm.
• The developed filter media met N95 performance targets for filtration efficiency and breathing resistance.
• Prototype duckbill-style respirators with PCL electrospun filters met N95 criteria.

Conclusions:

• Electrospun PCL nanofiber filters provide a biodegradable and high-performance alternative to conventional FFRs.
• Optimizing fiber diameter, solidity, and basis weight is key for achieving superior filtration with less material.
• These findings support the development of sustainable respirators meeting stringent safety standards.