Synthesis and Properties of Rigid-Rod Benzobisazole Polymers ContainingBenzothiazole Pendent Groups

摘要

Novel polybenzobisazoles containing benzothiazole pendents were prepared by thereaction of 2-benzothiazole or 2,5-dibenzothiazole terephthalic acids with the appropriate aminomercapto, aminohydroxy or tetraamino monomers in polyphosphoric acid at elevated temperatures. The polymerizations were carried out at concentrations (10-18%) which would promote anistropic reaction mixtures. Intrinsic viscosities in range of 4-19dl/g were measured in methanesulfonic acid at 30 C. Thermogravimetric-mass spectral analysis in vacuo showed that the pendent benzothiazole group was the initial product of thermal degradation, maximizing at 590 C. Anisotropic polymerization mixtures could be wet-spun into fiber with modulus values between 25-30 MSI and tenacity values up to 350 KSI.