film
Polyimide film is one of the earliest products of polyimide. It is used for slot insulation of motors and cable wrapping materials. The main products are Dupont Kapton, Upilex series produced by Ube and Zhongyuan Apical. The transparent polyimide film can be used as a soft solar cell bottom plate. IKAROS sails are made of polyimide films and fibers. Polyimide fibers can be used for hot gas filtration, and polyimide yarns can separate dust and special chemicals from exhaust gases.
Paint: used as an insulating paint for electromagnetic wires, or as a high temperature resistant paint.
Advanced composite materials: used in aerospace, aircraft and rocket components. It is one of the most high-temperature structural materials. For example, the supersonic airliner program in the United States has a designed speed of 2.4M, a surface temperature of 177 ° C during flight, and a required service life of 60,000h. It is reported that 50% of the structural materials have been determined to use thermoplastic polyimide as the matrix resin The carbon fiber reinforced composite material, the amount of each aircraft is about 30t.
Fiber: The modulus of elasticity is second only to carbon fiber. It is used as a filter material and bulletproof and fireproof fabric for high temperature media and radioactive materials. Changchun, China has various polyimide products.
Foam plastic: used as high temperature resistant heat insulation material.
Engineering plastics: there are thermosets and thermoplastics. Thermoplastics can be compression molded, injection molded or transfer molded. Mainly used for self-lubricating, sealing, insulating and structural materials. Guangcheng polyimide material has begun to be applied to mechanical parts such as compressor rotors, piston rings and special pump seals.
Separation membrane: used for separation of various gas pairs, such as hydrogen / nitrogen, nitrogen / oxygen, carbon dioxide / nitrogen or methane, etc., to remove water from air hydrocarbon feed gas and alcohol It can also be used as pervaporation membrane and ultrafiltration membrane. Because of its heat resistance and resistance to organic solvents, polyimide is of particular importance in the separation of organic gases and liquids.
Components and semiconductors
Photoresist: Some polyimides can also be used as photoresist. There are negative glue and positive glue, and the resolution can reach sub-micron level. It can be used for color filter with pigment or dye, which can greatly simplify the processing procedure.
Application in microelectronic devices: used as a dielectric layer for interlayer insulation, as a buffer layer can reduce stress and improve yield. As a protective layer, it can reduce the impact of the environment on the device, and can also shield the a-particles, reducing or eliminating the soft error of the device (soft error). The semiconductor industry uses polyimide as a high temperature adhesive. When producing digital semiconductor materials and MEMS system chips, the polyimide layer has good mechanical ductility and tensile strength, which helps to improve the polyimide layer And the adhesion between the polyimide layer and the metal layer deposited above. The high temperature and chemical stability of polyimide play a role in isolating the metal layer from various external environments.
Orientation aligning agent for liquid crystal display: Polyimide occupies a very important position in the aligning agent materials of TN-LCD, SHN-LCD, TFT-CD and future ferroelectric liquid crystal displays.
Electro-optical materials: used as passive or active waveguide materials, optical switch materials, etc., fluorine-containing polyimide is transparent in the communication wavelength range, and polyimide as the matrix of chromophore can improve the stability of the material Sex.
Moisture-sensitive material: It can be used to make a humidity sensor using its principle of hygroscopic linear expansion.