+1 Recommend
    • Review: found
    Is Open Access

    Review of 'The elastic modulus of isolated polytetrafluoroethylene filaments'

    The elastic modulus of isolated polytetrafluoroethylene filamentsCrossref
    Well designed study on a specific problem, is this approach more widely applicable?
    Average rating:
        Rated 4 of 5.
    Level of importance:
        Rated 3 of 5.
    Level of validity:
        Rated 4 of 5.
    Level of completeness:
        Rated 4 of 5.
    Level of comprehensibility:
        Rated 4 of 5.
    Competing interests:

    Reviewed article

    • Record: found
    • Abstract: found
    • Article: found
    Is Open Access

    The elastic modulus of isolated polytetrafluoroethylene filaments

    We report vibrational Raman spectra of small extended perfluoro-n-alkanes (C{n}F{2n+2} with n=6, 8-10, 12-14) isolated in supersonic jet expansions and use wavenumbers of longitudinal acoustic vibrations to extrapolate the elastic modulus of cold, isolated polytetrafluoroethylene filaments. The derived value E = 209(10) GPa defines an upper limit for the elastic modulus of the perfectly crystalline, non-interacting polymer at low temperatures and serves as a benchmark for quantum chemical predictions.

      Review information

      This work has been published open access under Creative Commons Attribution License CC BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Conditions, terms of use and publishing policy can be found at www.scienceopen.com.

      Review text

      Please consider the following:

      Comment 1: The authors state "This adds a gas phase perspective to polymer science which can be exploited for rigorous comparison
      between theory and experiment", but the conformational dynamics of many polymers are influenced by intermolecular interactions. Can this approach be applied to other polyalkanes, or even other polymers, to characterise their elastic modulii?

      Comment 2: How do the low frequency longitudinal bands compare with those from the corresponding bulk solid phase Raman spectra?

      Comment 3: Can molecular dynamics simulations be applied to these PTFE systems to verify that the conformation of the predicted low energy structure is significant?

      Comment 4: How is sample decomposition (and therefore sample integrity) monitored? How often was photodecomposition by the 18W laser detected (if at all)?


      Comment on this review