A molecular dynamics study of the thermal response of crystalline cellulose Iβ
- 416 Downloads
Molecular dynamics simulations were performed to better understand the atomic details of thermal induced transitions in cellulose Iβ. The latest version of the GLYCAM force field series (GLYCAM06) was used for the simulations. The unit cell parameters, density, torsion angles and hydrogen-bonding network of the crystalline polymer were carefully analyzed. The simulated data were validated against the experimental results obtained by X-ray diffraction for the crystal structure of cellulose Iβ at room and high temperatures, as well as against the temperature-dependent IR measurements describing the variation of hydrogen bonding patterns. Distinct low and high temperature structures were identified, with a phase transition temperature of 475–500 K. In the high-temperature structure, all the origin chains rotated around the helix axis by about 30° and the conformation of all hydroxymethyl groups changed from tg to either gt on origin chains or gg on center chains. The hydrogen-bonding network was reorganized along with the phase transition. Compared to the previously employed GROMOS 45a4 force field, GLYCAM06 yields data in much better agreement with experimental observations, which reflects that a cautious parameterization of the nonbonded interaction terms in a force field is critical for the correct prediction of the thermal response in cellulose crystals.
KeywordsCellulose Iβ Molecular dynamics GLYCAM06 Thermal response
This work was supported by a grant from the Swedish National Infrastructure for Computing (SNIC) for the project “Multiphysics Modeling of Molecular Materials”, SNIC 022/09-25 and by the Swedish Centre for Biomimetic Fibre Engineering (Biomime).
- Hirschfelder JO, Curtiss CF, Brid RB (1954) Molecular theory of gases and liquids. Wiley, New YorkGoogle Scholar
- Kirschner KN, Yongye AB, Tschampel SM, González-outeirtño J, Daniels CR, Lachele Foley B, Woods RJ (2008) GLYCAM06: a generalizable biomolecular force field. Carbohydr J Comput Chem 29:622–655Google Scholar
- Klemm D, Hans-Perter S, Heinze T (2002) In biopolymers—polysaccharides II. vol. 6, Steinbüchel A (ed). Wiley-VCH, WeinheimGoogle Scholar
- Lindahl E, Hess B, van der Spoel D (2001) GROMACS 3.0: a package for molecular simulation and trajectory analysis. J Mol Mod 7:306–317Google Scholar
- Pérez S, Mazeau K (2005) In: Dumitriu S (ed) Polysaccharides, structure and functional versatility, 2nd edn. Marcel Dekker, New York, pp 41–68Google Scholar
- Salmen L, Bergstrom E (2009) Cellulose structural arrangement in relation to spectral changes in tensile loading FTIR cellulose 16:975–982Google Scholar
- van der Spoel D, Lindahl E, Hess B, van Buuren AR, Apol E, Meulenhoff PJ, Tieleman DP, Sijbers ALTM, Feenstra KA, van Drunen R, Berendsen HJC (2005) Gromacs User Manual version 4.0 www.gromacs.org
- Vliegenthart JFG, Woods RJ (2006) NMR spectroscopy and computer modeling of carbohydrates: recent advances. American Chemical Society, Washington DC, pp 235–257Google Scholar
- Wada M, Kondo T, Okano T (2003) Thermally induced crystal transformation from cellulose Iα to Iβ. Polym J 35:155–159Google Scholar
- Wada M, Hori R, Kim UJ, Sasaki S (2010) X-ray diffraction study on the thermal expansion behavior of cellulose Iβ and its high-temperature phase. Polym Degrad Stabil 95:1330–1334Google Scholar
- Watanabe A, Morita S, Ozaki Y (2006b) Temperature-dependent structural changes in hydrogen bonds in microcrystalline cellulose studied by infrared and near-infrared spectroscopy with perturbation-correlation moving-window two-dimensional correlation analysis. Appl Spectrosc 60:611–618CrossRefGoogle Scholar