Polyimide fiber is a kind of aromatic heterocyclic organic fiber, which is one of the varieties with the best comprehensive performance among high-performance organic fibers. With the improvement of polyimide synthesis technology and the advancement of fiber spinning technology, the industrialization process of polyimide fibers with excellent properties such as radiation resistance, high temperature resistance, and high strength has gradually accelerated. , new building materials, environmental protection and fire prevention and other fields play an increasingly important role.

Preparation Process:

  There are mainly one-step and two-step spinning technology routes for the preparation of polyimide fibers. The two-step spinning route uses the polyamic acid solution as the spinning slurry to first prepare the polyamic acid fiber, and then obtain high-performance polyimide after thermal imidization, thermal stretching and heat treatment at a high temperature of 250~350 °C. fiber. Due to the good solubility of polyamic acid, the two-step process can well solve the problem of solvent selection in the production of polyimide fibers.

Performance:

(1) High strength and high modulus: the breaking strength can reach 4.6GPa;

(2) High temperature resistance: The initial decomposition temperature of PI is generally around 500 °C. The polyimide synthesized from biphenyl dianhydride and p-phenylenediamine has a thermal decomposition degree of 600°C;
(3) Low temperature resistance: Polyimide has excellent low temperature resistance, such as it will not be brittle in -269℃ liquid nitrogen;

(4) Good radiation resistance;

(5) Excellent dimensional stability;

(6) Biocompatibility: PI fiber has no biological toxicity and can withstand thousands of times of disinfection;

(7) PI has good dielectric properties, and the dielectric constant is around 3.4;

(8) PI fiber is a self-extinguishing polymer: the smoke generation rate is low.

Application areas:

  Polyimide fibers are currently mainly used in the following fields:

  One is the field of high-temperature filtration, which is used as a filter material for exhaust gas treatment bag filters in cement production and other fields;

  The second is in the field of special protection, manufacturing protective equipment under harsh conditions such as high temperature and strong radiation, such as fire-retardant and flame-retardant clothing, thermal insulation blankets, flight suits, high-voltage shielding clothing, high-temperature resistant special braided cables, etc.;
  The third is in the field of textile and clothing, which is made into outdoor cold-proof clothing, warm flakes, fleece clothing, etc.

  The application field of polyimide fiber is still gradually expanding, and the market demand in the fields of nuclear energy industry, space environment, aerospace, national defense and military industry, new construction, high-speed transportation, marine development, environmental protection, sports equipment, new energy, etc. The volume is also growing, and its market potential is huge.

  Facing the major needs of the country, it focuses on technology research and development and application in the field of environmental protection, and develops and innovates in the fields of industrial flue gas dust removal, denitrification, circular economy, and smart environmental protection; it is committed to leading the frontier of industry technology and promoting the integration of new formats in the environmental protection industry. The filter bag made of imide fiber has excellent performance and long service life, and is widely used in cement, steel and other industries.