1.Structural Properties of Polyimide Fibers
Polyimide fiber（ PI fiber）, commonly known as “Golden Fiber,” is a prominent variety of high-performance fiber characterized by a molecular backbone containing imide ring groups.
The backbones of typical polyimides feature an abundance of imide rings, aromatic rings, or heterocyclic rings;
This structural composition imparts high aromaticity and significant rigidity to the molecular chains.
Furthermore, the nitrogen-oxygen double bonds within the imide rings possess exceptionally high bond energies,
While the conjugated effects arising from the aromatic and heterocyclic rings result in strong intermolecular forces.
Theoretically, polyimide fiber can achieve a Young’s modulus of up to 410 GPa—a value surpassed only by carbon fiber.
Its tensile strength exceeds that of Kevlar 49 aramid fiber, and it boasts a higher modulus nearly on par with the “super fiber” PBO
While simultaneously exhibiting the defining characteristics of high strength, high modulus, and exceptional thermal stability.
2.Advantages and Applications of Polyimide Fibers
Given the performance advantages，inherent in PI fibers combined with my country’s strengths in the production technology for PI raw materials，
PI fibers hold immense promise for applications in the fields of industrial dust removal and aerospace.
Currently, within the industrial dust removal sector, baghouse filtration systems can utilize a variety of filter media;
However, the exceptional properties of PI fibers establish them as the optimal choice among contemporary baghouse filtration materials.
The high strength, high modulus, and unique irregular cross-sectional structure of PI fibers effectively guarantee the filtration efficiency and dust-capturing capacity of the filter media,
thereby extending their service life, reducing the frequency of replacements, and significantly lowering overall costs.
In the aerospace sector, as the demand for lightweight yet high-strength aircraft components continues to rise, the need for specialized fiber materials is steadily increasing.
Furthermore, PI fibers find extensive application in structural components and composite materials such as high performance thermal insulation, electrical insulation, and high-performance reinforcement materials for rubber and plastics.
When processed into paper, polyimide fibers can be utilized to create high-performance insulating paper suitable for high-grade motor insulation;
when formed into honeycomb cores, they serve as key components in the manufacture of lightweight composite materials.
3.Summarize
Currently, my country leads the world in the research, development, and preparation technologies for polyimide fibers; however,
significant work remains to be done such as further enhancing and stabilizing performance, as well as expanding production scale and reducing costs.
Concurrently, it is essential to strengthen fundamental research into applications, leveraging the inherent structural designability
and tunable properties of polyimides to research and develop functional polyimide fibers, thereby meeting the diverse application demands across various fields.