Research on Van der Waals and Electrostatic Interaction of Cellulose Iα Based on Molecular Dynamics Simulation

As can be observed on our previous works on cellulose I beta, Van der Waals and (VDW) electrostatic interaction (ELE) are indispensable for the stability of different sheets. In light of this, cellulose I alpha was selected as a research object to better understand the properties of native cellulose. With comparatively agreeable results to previous researches, the mean interactions of VDWand ELE per chain were determined to be -131.68 and -56.38 Kcal/mol respectively. The interactions VDW and ELE in cellulose I alpha per chain always decreased with the rise in temperature. Whereas, for cellulose I beta, the Van der Waals energy gradually reduced from 298 K to 400 K, then remained unchanged. The electrostatic energy increased initially, then decreased as the temperature ascended. The computation results indicate that the stratified interactions (intrachain, interchain and intersheet) are observed to be less than cellulose I beta. Nevertheless, the intersheet interactions in cellulose I alpha are comparable with cellulose I beta, especially for Van der Waals interaction. With quantitative analysis, the stability mechanism in cellulose I alpha is revealed to be different to I beta. The interaction VDW has a better performance at high temperature for intersheet and interchain structure.