Quantitative Viscoelastic Mapping of Cellulose Nanofibrils Using Low-Total-Force Contact Resonance Force Microscopy (LTF-CRFM)

Published

May 26, 2022

Author(s)

Kristen Hess, Jason Killgore, Wil Srubar

Abstract

Low-total-force contact resonance force microscopy (LTF-CRFM), an atomic force microscopy method, is introduced as a means to quantify the local viscoelastic loss tangent of cellulose nanofibrils (CNFs). The method limits static and dynamic forces during measurement to minimize substrate and geometry effects and reduce potential for stress-induced fibril damage. LTF-CRFM uses Brownian motion to achieve the thermally limited lowest dynamic force, while approaching adhesive pull-off to achieve the low static force. The LTF-CRFM measurements were shown to generate analyzable data without evidence of nonlinear artifacts and without damage to the CNF over static forces ranging from 11.6 nN to 84.6 nN. The measured tan⁡δ of CNFs was 0.015 ± 0.0094, which is the first reported tan⁡δ measurement of an isolated CNF. Finally, LTF-CRFM successfully mapped tan⁡δ along the length of CNFs to assess whether kink defects along the CNF imparted a local viscoelastic property change. However, no significant change in tan⁡δ in the transverse CNF direction was observed at the length scale of the measurement.

Citation

Cellulose

Volume

29

Pub Type

Journals

Download Paper

https://doi.org/10.1007/s10570-022-04603-9

Local Download

Citation

Hess, K. , Killgore, J. and Srubar, W. (2022), Quantitative Viscoelastic Mapping of Cellulose Nanofibrils Using Low-Total-Force Contact Resonance Force Microscopy (LTF-CRFM), Cellulose, [online], https://doi.org/10.1007/s10570-022-04603-9, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=932650 (Accessed October 8, 2025)