Effects of Moisture on the Mechanical Properties of Microcrystalline Cellulose and the Mobility of the Water Molecules as Studied by the Hybrid Molecular Mechanics-Molecular Dynamics Simulation Method
Effects of Moisture on the Mechanical Properties of Microcrystalline Cellulose and the Mobility of the Water Molecules as Studied by the Hybrid Molecular Mechanics-Molecular Dynamics Simulation Method
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DOI：
10.1002/polb.24801
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发表时间：
2019-02
期刊：
影响因子：
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通讯作者：
I. H. Sahputra;A. Alexiadis;M. Adams
中科院分区：
文献类型：
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作者：
I. H. Sahputra;A. Alexiadis;M. Adams
采用分子力学-分子动力学混合模拟方法研究了水分含量对微晶纤维素（MCC）力学性能和水分子运动性的影响。在1. 8 - 25. 5 w/w %的研究范围内，水的比体积和扩散系数随着含水量的增加而增加，而杨氏模量则降低。模拟结果与实验数据吻合较好。水对MCC的增塑作用是由束缚断裂机制和自由体积机制共同作用的结果。Voronoi体积随着含水量的增加而增加。它与自由体积有关，自由体积的增加增强了水分子的流动性，从而增加了水的扩散系数。此外，随着水分含量的增加，MCC -水分子之间的每个水分子的氢键减少，从而增加了水的流动性和游离水分子的数量。© 2019作者Journal of Polymer Science Part B：Polymer Physics，Wiley Periodicals，Inc. J. Polym.科学，部分B：聚合物物理2019，57，454 - 464
: A hybrid molecular mechanics – molecular dynamics simulation method has been performed to study the effects of moisture content on the mechanical properties of microcrystalline cellulose (MCC) and the mobility of the water molecules. The speci fi c volume and diffusion coef fi cient of the water increase with increasing moisture content in the range studied of 1.8 – 25.5 w/w %, while the Young ’ s modulus decreases. The simulation results are in close agreement with the published experimental data. Both the bound scission and free-volume mechanisms contribute to the plasticization of MCC by water. The Voronoi volume increases with increasing moisture content. It is related to the free volume and the increase enhances the mobility of the water molecules and thus increases the coef fi cient of diffusion of the water. Moreover, with increasing moisture content, the hydrogen bonding per water molecule between MCC – water molecules decreases, thus increasing the water mobility and number of free water molecules. © 2019 The Authors. Journal of Polymer Science Part B: Polymer Physics published by Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57 , 454 – 464