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Multi-functional air filters with excellent flame retardancy and fire-warning capability
Tienan Zhao1, Defang Teng1, Yuanqiang Xu1
1College of Textiles, Donghua University, Shanghai 201620, China.
Journal of Colloid and Interface Science
|March 13, 2022
Summary
New air filters combine flame retardancy and fire warning. These advanced filters, using Polyacrylonitrile (PAN), ammonium polyphosphate (APP), and amino-functionalized carbon nanotubes (A-CNTs), offer superior protection for indoor environments.
Area of Science:
- Materials Science
- Chemical Engineering
- Environmental Science
Background:
- High fire-safe air filters are crucial for indoor environments like vehicles and buildings.
- Existing filters face challenges in balancing flame retardancy with rapid fire-warning capabilities.
Purpose of the Study:
- To fabricate high-efficiency fiber filters with combined flame-retardant and fire-warning performance.
- To develop multifunctional air filters for enhanced safety in various applications.
Main Methods:
- Designed nanofibers with a tri-layer structure using Polyacrylonitrile (PAN) matrix.
- Incorporated flame retardant ammonium polyphosphate (APP) and amino-functionalized carbon nanotubes (A-CNTs).
- Tested filters for PM2.5-10 capture efficiency, flame retardancy (vertical burning test, limiting oxygen index), and fire-warning response time.
Main Results:
- Achieved high PM2.5-10 capture efficiency of >99.99%.
- Demonstrated excellent flame retardancy, not burning in vertical tests and achieving a limiting oxygen index of 30.9%.
- Exhibited a rapid fire-warning response time of approximately 5 seconds.
Conclusions:
- Developed a facile and cost-effective method for fabricating multifunctional air filters.
- The PAN/CNTs/APP fiber filters show significant promise for applications in vehicle interiors, firefighting, fresh air systems, and building materials.
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