The role of the hydrogen bonding network for the shear modulus of PIPD

Tumor microenvironmental genomic alterations in juvenile nasopharyngeal angiofibroma

“…Initially, X‐ray diffraction studies performed by Klop and Lammers6 indicated that the intermolecular H‐bonds formed a bi‐directional network in which a polymer chain is linked to four axially shifted neighboring chains. However, a study by Hageman et al7 based on ab initio energy calculations indicates that a sheet‐like H‐bonded network is more likely. Both studies agree that the presence of a network of intermolecular H‐bonds has a direct impact on the compressive properties of the fiber.…”

Polybenzobisimidazole‐derived two‐dimensional supramolecular polymer

“…To construct a periodic alignment of PBBI, we referred to the structural analyses of poly(pyridobisimidazole) that is very similar to PBBI except for the position of one hydroxyl group and the pyridine moiety . (c), Based on the information of bond lengths and unit cell (either monoclinic or triclinic) of poly(pyridobisimidazole), (c) we indexed a = 16.67 Å and b = 6.63 Å for SP‐PBBI parameters [Fig. (d)].…”

Effect of hydration on the structures and properties of poly(p-phenylene benzobisoxazole)/poly(pyridobisimidazole) block copolymer fibers

“…This can be explained by the forming of hydrogen bonds between the adjacent chains due to the introduction of PIPD segments into the main chains. [23][24][25] As the mole ratio between PBO segments and PIPD segments decreases below 5/1, the tensile modulus of PBO-b-PIPD fibers begin to decrease obviously, and this can be attributed to more disordered packing of PBO-b-PIPD chains with higher content of PIPD segments, which can be confirmed by the WAXD patterns shown in Figure 6. As for PBO-b-PIPD (5/3) fibers, the degree of chaos in chain arrangement becomes severe, which shows the lowest tensile modulus, which is even lower than that of PBO fibers.…”