Abstract

Spectroscopic studies have been carried out on aromatic polyamide (PA) solutions in sulphuric acid. The large enthalpies of complexing (167–230 kJ/unit) indicate that an ionized polymer exists. PA concentrates have shown anisotropy of IR-radiation absorption for amide I and II which has an unusual π-polarization of the amide I line; this indicates the possibility of an imidol-type of PA forming in the solution. The likely shapes of the PA chains and types of intermolecular bonds present in the polymer-polymer and polymer-solvent systems have been examined. Two types of crystal solvates with trans- and cis-conformations of the amidol groups are suggested; these are under stress due to ionic-type intermolecular bonds between the polymer and the sulphuric acid. The formation of a mesomorphic state is associated with the existence of polymer-polymer aggregates having the normal δ-polarization of the amide I line. The part played by the intermolecular H-bond during the realization of the liquid-crystalline state of the aromatic PA solutions is assessed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.