title: Synthesis and properties of poly[p-(2,5-dihydroxy)-phenylenebenzobisoxazole] fiber.
abstract: The novel polymer poly[p-(2,5-dihydroxy)-phenylenebenzobisoxazole] (PBOH) fiber was synthesized in the presence of 2,5-dihydroxyterephthalicacid (DHTA) and 4,6-diamino-1,3-benzenediol in poly(phosphoric acid) (PPA) using typical polycondensation conditions. The crystalline solutions of liquid PBOH in PPA were spun into fibers using dry-jet wet spinning. Furthermore, the thermostability and mechanical properties of PBOH were compared with poly(p-phenylene-2,6-benzoxazole) (PBO) in order to investigate the relationship between the chain structure and properties. The results indicated that the thermal degradation temperature of PBOH was above 750K and the tensile strength of the PBOH fiber was 3.1GPa, which were much lower than those of PBO fiber. The compressive strength of PBOH fiber was 331 M Pa, which was slightly higher than that of PBO fiber. In addition, molecular simulation was employed to explain why the compressive strength of PBOH fiber did not increase significantly compared to PBO fiber.
authors.affiliation: Department of Applied Chemistry, Faculty of Science, Harbin Institute of Technology, Harbin 150001, P.R. China.
authors.forename: Hong
authors.initials: H
authors.lastname: Lin
authors.affiliation: Department of Applied Chemistry, Faculty of Science, Harbin Institute of Technology, Harbin 150001, P.R. China.
authors.forename: Yu-Dong
authors.initials: YD
authors.lastname: Huang
authors.affiliation: Department of Applied Chemistry, Faculty of Science, Harbin Institute of Technology, Harbin 150001, P.R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang