物理改性纤维素绝缘材料亲水性行为的分子动力学模拟  

Molecular Dynamics Simulation on the Hydrophilicity of Physical Modification Cellulose Insulating Materials

作　　者：廖瑞金[1] 聂仕军[1] 周欣[1] 朱孟兆 袁磊[1] 杨丽君[1] 

机构地区：[1]重庆大学输配电装备及系统安全与新技术国家重点实验室,重庆400030 [2]山东电力科学研究院,济南250002

出　　处：《高电压技术》2013年第1期1-7,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209401);国家创新研究群体基金(51021005);国家自然科学基金(51077136)~~

摘　　要：为了从微观层次揭示物理改性后纤维素绝缘材料抗老化性能提高的机理,选用聚合度为3的纤维素分子链、水分子、三聚氰胺和双氰胺分别对改性前后纤维素材料的无定形区进行了建模,并用分子动力学模块对这2个模型进行了计算。分别从水分的扩散系数、体系内的氢键结合数和分子之间的相互作用能3个方面探讨了改性前后体系的变化和抗老化性能差异的作用机理。结果发现:物理改性体系中的水分子扩散系数小于天然体系;由于抗老化剂的作用,物理改性体系中的总氢键数多于天然体系。与水分子的相互作用能上,抗老化剂最大,天然纤维素分子次之,改性体系中的纤维素分子最小;抗老化剂的存在使纤维素分子与水分子的相互作用能减弱。In order to reveal the micro mechanism of anti-aging performance improvement in physical modification cellulose insulating materials,we established two models of the amorphous area of cellulose material before and after modification（with cellulose,water,melamine and dicyandiamide）,respectively,and calculated the two models using molecular dynamics methods.System variations after the modifications were investigated from three aspects,namely,water diffusion coefficients,number of hydrogen bonding,and interaction energy.The three parameters were also adopted to figure out the reasons of differences in anti-aging properties between the two models.Simulation results indicate that the diffusion coefficient of physical modification systems is less than that of natural system,but owing to the inhibitor,the total number of hydrogen bond of modified systems exceeds that of natural system.As for the interaction energy with water molecules,inhibitor has the maximum value,while natural cellulose molecules has a smaller value and cellulose molecule of modified system has the minimum value.In existence of inhibitor,the interaction energy between cellulose molecules and water molecules decreases.

关 键 词：分子动力学 纤维素 亲水性 浸油绝缘纸 物理改性 热稳定纸 

分 类 号：TM21[一般工业技术—材料科学与工程]