PI film production machine line

Polyimide film (PolyimideFilm) is the world's best performance film insulating materials, by the benzene tetracarboxylic acid dianhydride and diaminodiphenyl ether in a strong polar solvent by polycondensation and casting into a film and then imidization.

Polyimide advantages

(1) excellent heat resistance. Polyimide decomposition temperature is generally more than 500 ℃, sometimes even higher, is known to be one of the highest thermal stability of organic polymers, mainly because the molecular chain contains a large number of aromatic rings.

(2) Excellent mechanical properties. The tensile strength of the unreinforced matrix material are above 100MPa. Kapton film prepared with uniform anhydride tensile strength of 170MPa, and biphenyl polyimide can reach 400MPa. polyimide fiber modulus of elasticity can reach 500MPa, second only to carbon fiber.

(3) Good chemical stability and resistance to moisture and heat. Polyimide materials are generally insoluble in organic solvents, corrosion resistance, hydrolysis resistance. Change the molecular design can be obtained from different structural varieties. Some varieties withstand 2 atmospheric pressure, 120 ℃, 500h of boiling.

(4) good radiation resistance. Polyimide film in 5 × 109rad dose radiation, the strength is still maintained 86%; some polyimide fiber by 1 × 1010rad fast electron radiation, its strength retention rate of 90%.

(5) good dielectric properties. Dielectric constant is less than 3.5, if the introduction of fluorine atoms in the molecular chain, the dielectric constant can be reduced to about 2.5, dielectric loss of 10, dielectric strength of 100 to 300kV/mm, volume resistance of 1015-17Ω-cm. Therefore, the synthesis of fluorine-containing polyimide materials is a more popular research areas.

Fields of application

(1) Film: It is one of the earliest products of polyimide and is used for slot insulation of motors and cable winding materials. The main products are DuPont's Kapton, Japan's Upilex series of UBE and Apical of Zhong Yuan. Transparent polyimide film can be used as a flexible solar cell substrate.

(2) Coatings: Used as insulating varnish for electromagnetic wires, or as high-temperature resistant coatings.

(3) Matrix resins for advanced composite materials: used in aerospace and defense applications.

(4) fiber: polyimide fiber modulus of elasticity second only to carbon fiber, can be used as a high-temperature media and radioactive material filtering materials and bullet-proof fire fabrics.

(5) Foam: can be used as heat-resistant insulation materials.

(6) engineering plastics: thermosetting and thermoplastic, can be molded or injection molding or transfer molding (RTM), mainly for self-lubricating, sealing, insulation and structural materials. In addition, polyimide can also be used as an adhesive in high temperature environments, separation film, photoresist, dielectric buffer layer, liquid crystal orientation agent, electric - optical materials.

Polyimide Prospects

Polyimide has been well recognized as a promising polymer material, and its applications in insulating materials and structural materials are expanding. It is emerging as a functional material, and its potential is still being explored.