It is a reinforcing material of composite materials developed by the United States in the 1980s for the development of aerospace industry. It is the most promising member of polyamide family containing heterocyclic aromatic compounds and is known as 2 1 century super fiber.
Development history
PBO was invented by air force aerodynamics researchers. At first, the basic patent of polybenzoxazole was owned by Stanford University Research Institute (SRI), and later Dow Chemical Company was authorized to industrially develop PBO. At the same time, the synthesis method of original monomer was improved, and the new process hardly produced isomer by-products, which improved the yield of synthetic monomer and laid the foundation for industrialization. 1990 Toyo Textile Company of Japan purchased PBO patented technology from Dow Chemical Company of the United States.
199 1 year, Yi Dao Badish chemical fiber company developed PBO fiber on the equipment of Toyo Textile Company, which greatly improved the strength and modulus of PBO fiber, reaching twice that of PPTA fiber.