Abstract
Atomic force microscopy (AFM) images obtained from cleaved surfaces of both as-spun and annealed fibers of poly(p-phenylene terephthalamide) (PPTA) have been interpreted with the aid of results from molecular simulations and wide angle X-ray scattering (WAXS). Angstrom-scale periodicities observed in AFM images of the annealed fiber are in accord with those reported in the literature based on WAXS data. For the as-spun fiber, AFM confirms the presence of at least two polymorphs. Among these, a new lattice structure is observed, which has eluded deconvolution from experimental X-ray data. This new lattice exhibits chain conformations and hydrogen bonding structure which is distinct from that seen in either of the two previously reported crystal modifications of PPTA. Interpretation of the AFM images in this case is greatly facilitated by the independent data from molecular simulations. The new crystal facet observed is fully consistent with a third crystal modification previously suggested by molecular simulation.
Sign-in/Register to access full text options 
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 callDisclaimer: 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.
