PBO materials possess super mechanical properties and high thermal and chemical resistance due to their special rigid-rod backbones with heterocyclic chemical structure and supermolecular microstructure. But these str...PBO materials possess super mechanical properties and high thermal and chemical resistance due to their special rigid-rod backbones with heterocyclic chemical structure and supermolecular microstructure. But these structures may be affected by a series of preparing technologies, among which the coagulant is even more important. In this paper the chemical and microstructure changes of PBO materials coagulated with different solvents were investigated. Analyses of molecular weight and chemical structure of PBO coagulated indicate that the heterocyclic ring of PBO will experience cleavage in coagulation and in this stage water plays an important role. The final structure of PBO materials may involve several intermediate structures lying between benzoxazole and the open ring. Wide-angle X-ray diffraction (WAXD) 2θ scans and scanning probe microscope (SPM) show that the microstructure of PBO materials coagulated in solvents with different properties will change a lot and those coagulants with the smaller rate of diffusion like methanol can cause more ordered molecule alignment containing fewer voids.展开更多
In this work, the surface modification of poly （1, 4-phenylene-cis-benzobisoxazole） （PBO） fibers by O 2 /Ar coaxial atmospheric dielectric barrier discharge was investigated, as well as the interfacial adhesion pr...In this work, the surface modification of poly （1, 4-phenylene-cis-benzobisoxazole） （PBO） fibers by O 2 /Ar coaxial atmospheric dielectric barrier discharge was investigated, as well as the interfacial adhesion properties of modified PBO fibers/epoxy composites. The results indicated that the contact angle decreased remarkably from 84.7 to 63.5 after 3 min O 2 /Ar plasma treatment. SEM and AFM images showed that the surface of the treated PBO fibers became rather rough. In addition, XPS results suggested that the polar functional group （O=C- O） was introduced on the surface of the treated PBO fiber. The interfacial adhesion test showed that the interfacial shear strength （IFSS） and the interlaminar shear strength （ILSS） increased significantly by 63.54% and 130%, respectively. Moreover, the excellent tensile property of the PBO fibres was well preserved.展开更多
基金Sponsored by the National High Technology Research and Development Program of China(Grant No. 2002AA305109) and Innovational Project in Space Flight Science and Technology(Grant No.2409035).
文摘PBO materials possess super mechanical properties and high thermal and chemical resistance due to their special rigid-rod backbones with heterocyclic chemical structure and supermolecular microstructure. But these structures may be affected by a series of preparing technologies, among which the coagulant is even more important. In this paper the chemical and microstructure changes of PBO materials coagulated with different solvents were investigated. Analyses of molecular weight and chemical structure of PBO coagulated indicate that the heterocyclic ring of PBO will experience cleavage in coagulation and in this stage water plays an important role. The final structure of PBO materials may involve several intermediate structures lying between benzoxazole and the open ring. Wide-angle X-ray diffraction (WAXD) 2θ scans and scanning probe microscope (SPM) show that the microstructure of PBO materials coagulated in solvents with different properties will change a lot and those coagulants with the smaller rate of diffusion like methanol can cause more ordered molecule alignment containing fewer voids.
基金supported by Shanghai Composite Company and partially by National Natural Science Foundation of China (No.10875146)
文摘In this work, the surface modification of poly （1, 4-phenylene-cis-benzobisoxazole） （PBO） fibers by O 2 /Ar coaxial atmospheric dielectric barrier discharge was investigated, as well as the interfacial adhesion properties of modified PBO fibers/epoxy composites. The results indicated that the contact angle decreased remarkably from 84.7 to 63.5 after 3 min O 2 /Ar plasma treatment. SEM and AFM images showed that the surface of the treated PBO fibers became rather rough. In addition, XPS results suggested that the polar functional group （O=C- O） was introduced on the surface of the treated PBO fiber. The interfacial adhesion test showed that the interfacial shear strength （IFSS） and the interlaminar shear strength （ILSS） increased significantly by 63.54% and 130%, respectively. Moreover, the excellent tensile property of the PBO fibres was well preserved.
