Irregular and suppressed elastic deformation by a structural twist in cellulose nanofibre models

Abstract

The elastic responsiveness of single cellulose nanofibres is important for advanced analysis of biological tissues and their use in sophisticated functional materials. However, the mechanical responsiveness derived from the twisted structure of cellulose nanofibres (CNFs) has remained unexplored. In this study, finite element simulations were applied to characterize the deformation response derived from the torsional structure by performing tensile and bending tests of an unconventionally very long and twisted rod model, having the known dimensional parameters and properties of CNFs. The antagonistic action of two types of structural elements (a contour twist and a curvilinear coordinate) was found to result in an irregular deformation response but with only small fluctuations. The contour twist generated rotational displacements under tensile load, but the curvilinear coordinate suppressed rotational displacement. Under bending stress, the contour twist minimized irregular bending deformation because of the orthotropic properties and made the bending stress transferability a highly linear response.

Strong attractive interaction between finite element models of twisted cellulose nanofibers by intermeshing of twists

“…The COMSOL model (COMSOL Multiphysics 5.5, COMSOL Inc., Stockholm, Sweden) reported in a previous study 24 was used as the finite element model for the wooden twisted CNF. In brief, the hexagonal cross section of the 18-chained CNF model and its dimensions 2 were formed on the yz plane and swept for a 360° right-handed twist for a sweep length of 232 nm 9 in the x -axis direction.…”

Rheological Properties of Nanocellulose Dispersions in the Dilute Region: Current Understanding and Future Perspectives

“…This makes it more complicated to investigate the internal motions of CNFs. Recently, properties of single cellulose nanofibrils, such as structures of twisted and kinked regions, as well as elastic responses, have been extensively studied using microscopy and simulations 37,45,48,[51][52][53] . These findings on single cellulose nanofibrils will aid in clarifying the overall viscoelastic relaxation of CNFs.…”

Azobenzene-decorated cellulose nanocrystals as photo-switchable chiral solutes in nematic liquid crystals

“…19 The final nanocrystals are composed of chiral β(1 → 4) d -glucose subunits, which render CNCs structurally chiral with a twist in both their internal structure and their outer morphology, either on at individual NC or at the formed bundle level. 20–30 Their core chirality together with their rod-like shape enable CNCs to self-assemble into left-handed chiral nematic liquid crystal (N*-LC) phases, when dispersed in various solvents (commonly water) or after solvent evaporation. 31–40…”

“…19 The final nanocrystals are composed of chiral b(1 -4) D-glucose subunits, which render CNCs structurally chiral with a twist in both their internal structure and their outer morphology, either on at individual NC or at the formed bundle level. [20][21][22][23][24][25][26][27][28][29][30] Their core chirality together with their rod-like shape enable CNCs to self-assemble into lefthanded chiral nematic liquid crystal (N*-LC) phases, when dispersed in various solvents (commonly water) or after solvent evaporation. [31][32][33][34][35][36][37][38][39][40] To further enhance the versatility of hydrophobic CNCs as chiral solutes inducing N*-LC phases, the next logical step seemed to decorate CNCs with photoswitchable molecules that allow for the 'active' control (switching) of p, thus b w , by altering the wavelength of light irradiation.…”