Cellulose nanofiber (CNF) is a fibrous and nano-sized substance produced by decomposition of bulk-type cellulose which is a main component of plants. It has high strength comparable to steel, and it shows low environmental load during a cycle of production and disposal. Besides it has many excellent properties and functions such as high rigidity, light-weight, flexibility and shape memory effect, so it is expected as a next-generation new material. Usually it is composed of many cellulose micro fibrils (CMFs) in which molecular chains of cellulose are aggregated in a crystal structure, the knowledge of mechanical properties for each CMF unit is important. Since actual fibrils are complicatedly intertwined, it is also crucial to elucidate the transmission mechanism of force and deformation not only in one fibril but also in between fibrils. How the dynamic and hierarchical structure composed of CMFs responds to bending or torsion is an interesting issue. However, little is known on torsional characteristics (shear modulus, torsional rigidity, etc.) concerning CMF. In general, in a wire-like structure, it is difficult to enhance torsional rigidity and strength, compared with tensile ones. Therefore, in this study, we try to build a hierarchical model of CNF by multiplying CMF fibers and to conduct molecular dynamics simulation for torsional deformation, by using hybrid model between all-atom and united-atoms model. First, shear modulus was estimated for one CMF fibril and it showed a value close to the experimental values. Also, we assume a state in which two CMFs are ideally arranged in parallel, and create a hierarchical structure. We evaluate the dependence on the temperature for the bond strength and toughness in the hierarchical structures. Furthermore, we mentioned the transmission mechanism between components of a hierarchical structure.
References
[1]
Klemm, D., Kramer, F., Moritz, S., Lindström, T., Ankerfors, M., Gray, D. and Dorris, A. (2011) Nanocelluloses: A New Family of Nature-Based Materials. Angewandte Chemie International Edition, 50, 5438-5466. https://doi.org/10.1002/anie.201001273
[2]
Moon, R.J., Martini, A., Nairn, J. Simonsen, J. and Youngblood, J. (2011) Cellulose Nanomaterials Review: Structure, Properties and Nanocomposites. Chemical Society Reviews, 40, 3941-3994. https://doi.org/10.1039/c0cs00108b
[3]
Lee, K.-Y., Aitomäki, Y., Berglund, L.A., Oksman, K. and Bismarck, A. (2014) On the Use of Nanocellulose as Reinforcement in Polymer Matrix Composites. Composites Science and Technology, 105, 15-27. https://doi.org/10.1016/j.compscitech.2014.08.032
[4]
Milanez, D.H., Morato do Amaral, R., Lopes de Faria, L.I. and Gregolin, J.A.R. (2013) Technological Indicators of Nanocellulose Advances Obtained from Data and Text Mining Applied to Patent Documents. Materials Research, 16, 635-641. https://doi.org/10.1590/1516-1439.266314
[5]
Guhados, G., Wan, W. and Hutter, J.L. (2005) Measurement of the Elastic Modulus of Single Bacterial Cellulose Fibers Using Atomic Force Microscopy. Langmuir, 21, 6642-6646. https://doi.org/10.1021/la0504311
[6]
Wu, X., Moon, R.J. and Martini, A. (2014) Nanomechanical Properties of Cellulose Nanofibrils (CNF). Cellulose, 21, 2233-2245. https://doi.org/10.1557/adv.2015.30
[7]
Heiner, A.P. and Teleman, O. (1996) Comparison of the Interface between Water and Four Surfaces of Native Crystalline Cellulose by Molecular Dynamics Simulations. Pure and Applied Chemistry, 68, 2187-2192. https://doi.org/10.1351/pac199668112187
[8]
Yui, T., Nishimura, S., Akiba, S. and Hayashi, S. (2006) Swelling Behavior of the Cellulose Iβ Crystal Models by Molecular Dynamics. Carbohydrate Research, 341, 2521-2530. https://doi.org/10.1016/j.carres.2006.04.051
[9]
Nishiyama, Y., Johnson, G.P. and French, A.D. (2012) Diffraction from Nonperiodic Models of Cellulose Crystal. Cellulose, 19, 319-336. https://doi.org/10.1007/s10570-012-9652-1
[10]
Hadden, J.A., French, A.D. and Woods, R.J. (2014) Effect of Microfibril Twisting on Theoretical Powder Diffraction Patterns of Cellulose Iβ. Cellulose, 21, 879-884. https://doi.org/10.1007/s10570-013-0051-z
[11]
Shklyaev, O.E., Kubicki, J.D., Watts, H.D. and Crespi, V.H. (2014) Constraints on Iβ Cellulose Twist from DFT Calculations of 13C NMR Chemical Shifts. Cellulose, 21, 3979-3991. https://doi.org/10.1007/s10570-014-0448-3
[12]
Uto, T., Mawatari, S. and Yui, T. (2014) Theoretical Study of the Structural Stability of Molecular Chain Sheet Models of Cellulose Crystal Allomorphs. The Journal of Physical Chemistry B, 118, 9313-9321. https://doi.org/10.1021/jp503535d
[13]
Paavilainen, S., Róg, T. and Vattulainen, I. (2011) Analysis of Twisting of Cellulose Nanofibrils in Atomistic Molecular Dynamics Simulations. The Journal of Physical Chemistry B, 115, 3747-3755. https://doi.org/10.1021/jp111459b
[14]
Northolt, M.G., Boerstoel, H., Maatman, H., Huisman, R., Veurink, J. and Elzerman, H. (2001) The Structure and Properties of Cellulose Fibres Spun from an Anisotropic Phosphoric Acid Solution. Polymer, 42, 8249-8264. https://doi.org/10.1016/S0032-3861(01)00211-7
[15]
Zhao, Z., Shklyaev, O.E., Nili, A., Mohamed, M.N.A., Kubicki, J.D., Crespi, V.H. and Zhong, L. (2013) Cellulose Microfibril Twist, Mechanics, and Implication for Cellulose Biosynthesis. The Journal of Physical Chemistry A, 117, 2580-2589. https://doi.org/10.1021/jp3089929
[16]
Kannam, S.K., Oehme, D.P., Dobblin, M.S., Gidley, M.J., Bacic, A. and Downton, M.T. (2017) Hydrogen Bonds and Twist in Cellulose Microfibrils. Carbohydrate Polymers, 175, 433-439. https://doi.org/10.1016/j.carbpol.2017.07.083
[17]
Wang, J.-S., Wang, G., Feng, X.-Q., Kitamura, T., Kang, Y.-L., Yu, S.-W. and Qin, Q.-H. (2013) Hierarchical Chirality Transfer in the Growth of Towel Gourd Tendrils. Scientific Reports, 3, Article No. 3102. https://doi.org/10.1038/srep03102
[18]
Neyertz, S., Pizzi, A., Merlin, A., Maigret, B., Brown, D. and Deglise, X. (2000) A New All-Atom Force Field for Crystalline Cellulose I. Journal of Applied Polymer Science, 78, 1939-1946. https://doi.org/10.1002/1097-4628(20001209)78:11<1939::AID-APP130>3.0.CO;2-9
[19]
Neyertz, S. and Brown, D. (1995) A Computer Simulation Study of the Chain Configurations in Poly (Ethylene Oxide)-Homolog Melts. The Journal of Chemical Physics, 102, 9725-9735. https://doi.org/10.1063/1.471829
[20]
Koyama, A., Yamamoto, T., Fukao, K. and Miyamoto, Y. (2001) Molecular Dynamics Studies on Local Ordering in Amorphous Polyethylene. The Journal of Chemical Physics, 115, 560-566. https://doi.org/10.1063/1.1378068
[21]
Saitoh, K., Ohno, H. and Matsuo, S. (2013) Structure and Mechanical Behavior of Cellulose Nanofiber and Micro-Fibrils by Molecular Dynamics Simulation. Soft Nanoscience Letters, 3, 58-67. https://doi.org/10.4236/snl.2013.33011
