A simple and cost-effective method to produce high-performance robust heat-resistant paper by directly synthesizing polyimide within cellulose paper matrixes

Abstract

Robust heat-resistant paper, such as aramid sheet, is vital in both military and civilian applications. However, its production is hindered by complex processes and high costs, creating a need for simpler, more cost-effective manufacturing methods. Here, we present a simple and cost-effective method to produce high-performance robust heat-resistant paper by partially and directly synthesizing polyimide (PI) within cellulose paper matrixes. This method eliminates traditional aramid fiber pre-synthesis, fiber assembly, and subsequent paper formation steps, significantly simplifying production and reducing costs. The resulting PI/cellulose paper exhibits exceptional mechanical, thermal, and dielectric properties (strength: 89 MPa; maximum operating temperature: 240 °C; dielectric loss: 0.017 ∼ 0.004@1 ∼ 10⁶ Hz), comparable to those of commercial aramid Nomex T410 (strength: 80 MPa; maximum operating temperature: 240 °C; dielectric loss: 0.026 ∼ 0.012@1 ∼ 10⁶ Hz). Additionally, it demonstrates excellent flame retardancy, hydrophobicity, and moisture resistance. When utilized as lightweight honeycomb structural components and electrical insulating paper, it outperforms Nomex T410 in mechanical and electrical performance. Particularly, this method is simple, scalable, and cost-efficient, remarkably reducing production costs by approx.26.9 % compared to Nomex T410. With comparable or superior properties, coupled with simplified manufacturing processes and lower costs, this approach offers a promising pathway for the large-scale production of robust heat-resistant paper materials.