Binary Polyamide-Imide Fibrous Superelastic Aerogels for Fire-Retardant and High-Temperature Air Filtration

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Existing fibrous air filters struggle to balance high filtration efficiency with low pressure drop, especially for high-temperature industrial emissions.
• Achieving both small fiber diameters and high porosity simultaneously is a key challenge in developing advanced filtration materials.

Purpose of the Study:

• To develop mechanically robust fibrous aerogels for efficient particle removal from high-temperature industrial sources.
• To overcome the trade-off between filtration efficiency and pressure drop in current air filter technologies.

Main Methods:

• Fabrication of dual-scale fibrous aerogels using poly(amide-imide)/poly(benzoxazole-imide) (PAI/BMI) filaments via wet spinning and fibers via electrospinning.
• Utilizing PAI/BMI filaments as a reinforcing skeleton and PAI/BMI fibers to form a high-porosity network.

Main Results:

• The PAI/BMI fibrous aerogels exhibit excellent mechanical robustness with a compressive stress of 8.36 MPa.
• Achieved high filtration efficiency: 90.78% for 2.5 μm particles and 99.99% for particles > 5 μm.
• Demonstrated low pressure drop (20 Pa), high quality factor (QF = 0.12 Pa⁻¹), and superior thermal stability (decomposition temperature up to 342.7 °C).

Conclusions:

• The developed dual-scale PAI/BMI fibrous aerogels effectively address the limitations of conventional filters for high-temperature industrial dust control.
• This facile fabrication strategy offers a promising pathway for creating advanced, high-performance air filtration materials.