Journal ArticleDOI
Torsional Entropy at the Origin of the Reversible Temperature-Induced Phase Transition of Cellulose
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TLDR
In this paper, the temperature-induced phase transition of native cellulose was studied by X-ray diffraction and molecular dynamics (MD) simulation, and the phase transition was found to be irreversible in the MD simulation when using current GROMOS 53a6 force field parameters.Abstract:
The temperature-induced phase transition of native cellulose was studied by X-ray diffraction and molecular dynamics (MD) simulation. Upon heating, this transition is characterized by an important expansion of the distance between the planes of glucopyranose rings, which is observed both experimentally and in MD. Computed trajectories suggest that this expansion is caused by a rotation of the exocyclic hydroxymethyl groups. Upon cooling, the phase transition, experimentally known as reversible, was found to be irreversible in the MD simulation when using current GROMOS 53a6 force field parameters. By varying one of these, related to the potential energy of the hydroxymethyl conformers, a reversible phase transition could be observed in silico. From the linear dependence of the transition temperature on the dihedral energy of the different conformers, the entropy change due to the phase transition could be estimated to be about 26 JK–1 mol–1. This value essentially reflects the additive contribution of the...read more
Citations
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High temperature behavior of cellulose I
James F. Matthews,Malin Bergenstråhle,Malin Bergenstråhle,Gregg T. Beckham,Gregg T. Beckham,Gregg T. Beckham,Michael E. Himmel,Mark R. Nimlos,John W. Brady,Michael F. Crowley +9 more
TL;DR: In this article, the structural behavior of small hydrated cellulose Iβ microfibrils heated to 227 °C (500 K) with two carbohydrate force fields was investigated.
Journal ArticleDOI
A comparative molecular dynamics study of crystalline, paracrystalline and amorphous states of cellulose
Karol Kulasinski,Karol Kulasinski,Sinan Keten,Sergey V. Churakov,Dominique Derome,Jan Carmeliet,Jan Carmeliet +6 more
TL;DR: In this article, the authors apply united-atom molecular dynamics simulations to quantify changes in different morphologies of cellulose and reveal that the paracrystalline phase may be an intermediate, kinetically arrested phase formed upon amorphisation of crystalline cellulose.
Journal ArticleDOI
Deformation of cellulose nanocrystals: entropy, internal energy and temperature dependence
TL;DR: In this article, an in-depth analysis of the molecular deformation mechanisms in cellulose during axial stretching was performed, and it was demonstrated that entropy affects the stiffness of cellulose nanocrystals significantly.
Journal ArticleDOI
High-temperature decomposition of the cellulose molecule: a stochastic molecular dynamics study
Antti Paajanen,Jukka Vaari +1 more
TL;DR: In this paper, the authors carried out molecular dynamics simulations employing the ReaxFF reactive force field to study the initial step of the thermal decomposition process of cellulose pyrolysis at high temperatures, where the reaction rates are high enough to make the simulation times practical.
Journal ArticleDOI
Interfacial Adhesion of Polylactic Acid on Cellulose Surface: A Molecular Dynamics Study
TL;DR: This study provides a basic insight into the interfacial mechanisms of PLA and cellulose surfaces at the molecular level and shows improved adhesion to PLA due to enhanced hydrogen bonding.
References
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