Name | polyquinoxaline |
Synonyms | polyquinoxaline |
Physical and Chemical Properties | Chemical properties The most important characteristic of polyquinine polymers is high heat resistance, glass transition temperature 273-327 ℃, and stability at 400-450 ℃. Non-ether PPQ starts to decompose at 500 ℃ in the air and loses 1% heat at 550 ℃. 600 ℃,4%;900 ℃, only 24% weight loss. According to the existing data, PPQ is one of the varieties with the highest temperature resistance grade among aromatic heterocyclic high temperature resistant polymers. The temperature resistance reaches more than 1000h at 300 ℃ in air, and the hydrolysis performance is especially outstanding. The mechanical properties of polyquinine are also good, with room temperature bending strength of 686-768.32MPa and bending modulus of 25.01-2.67GPa (25.6-27.2). Thermal aging at 316 ℃ for 500h, bending strength greater than 343MPa. In the range of 20-200 ℃. The electrical performance changes very little. The dielectric constant of the film is 3.46 at room temperature and 3.22 at 194 ℃. The tangent value of dielectric loss angle is 6.10 at room temperature and the conductivity increases after 8.10 doping at 194 ℃. Quinoline can synthesize poly 2,6-[(4-phenyl) quinoline] in the presence of acidic catalyst Fried-iander. It is soluble and a high temperature resistant conductive polymer. It uses 4-chlorophenyl acetonitrile and 4-methoxyphenyl acetonitrile to synthesize poly 2,6-{4-chlorophenylquinoline and 2,6(4, 4-methoxyphenyl)} quinoline. The film of polyquinoline can be doped, and the solvent used is tetrahydrofurur or dimethoxyethane. The film is treated with sodium or potassium naphthalene compound or anthracene solution to obtain three structures of polyquinoline. |
Use | Uses polyquinoline is mainly used for adhesives, coatings, laminates, films and fibers. Because it can absorb a large amount of thermal energy or radiation energy without decomposition, it is a very promising high temperature heat screen material. |
Polyquinine is formed by solution polycondensation or melt polycondensation of o-tetraamine and tetracarbonyl compounds.
Solution polycondensation: Put tetramine I or II, tetracarbonyl compound III in a reaction kettle, use m-cresol or hexamethylphosphamide, dioxane, etc. as a solution, under the protection of inert gas at room temperature or 90 ℃ Reaction for several hours, add a precipitant such as methanol, precipitate the prepolymer, wash, dry, and then cyclize at 250-400 ℃ to obtain monoether, polyquinoline or di.
Melt polycondensation: Under the protection of inert gas, monomer I or II,III is added to the reaction kettle, melt polycondensation at 250 ℃ for several hours, and then heated to 350 ℃ under vacuum for dehydration and cyclization to obtain polyquinoline polymer. If biphenyltetramine and 1, 4-bisacetophenone benzene are used as raw materials to prepare non-ether polyphenylquinine [oral oxaline].