Si-GDP结构和力学性能的反应分子动力学模拟  

Reactive force field molecular dynamics simulation of structure andmechanical property of Si-doped glow discharge polymer

作　　者：黄保生 杨武 易勇[1] 毕鹏 Huang Baosheng;Yang Wu;Yi Yong;Bi Peng(School of Materials and Chemistry,Southwest University of Science and Technology,Mianyang 621010,China;School of Mathematics and Physics,Southwest University of Science and Technology,Mianyang 621010,China)

机构地区：[1]西南科技大学材料与化学学院,四川绵阳621010 [2]西南科技大学数理学院,四川绵阳621010

出　　处：《强激光与粒子束》2024年第6期74-80,共7页High Power Laser and Particle Beams

基　　金：四川省科技计划项目(2023NSFSC1990)。

摘　　要：构建了硅掺杂辉光放电聚合物(Si-GDP)模型,采用反应力场分子动力学模拟(ReaxFF MD)探讨了硅含量、碳氢比及密度对其杂化碳键合与力学性能的影响。研究结果表明:随着硅含量增加,聚合物中sp^(3)C含量增加,趋向于形成一个大分子,同时小分子种类和数目减少,促进了碳硅原子成键并抑制端基CH_(3)生成,进而提高材料力学性能;随着氢含量的增加,sp^(3)C和端基CH_(3)比例增加,生成的端基CH_(3)降低了分子间交联程度,进而降低了材料力学性能,而分子基团数目变化不明显;随着密度的提升,聚合物中sp^(2)C比例提升明显,sp^(3)C比例有少量提升,分子基团数目变化不大,密度主要通过提升sp^(2)C比例提升材料力学性能。研究结果为评估和理解硅掺杂辉光放电聚合物的结构和力学性能提供了新的视角和方法。The structural models of Si-doped glow discharge polymer(Si-GDP)were established using reactiveforce field molecular dynamics simulation(ReaxFF MD),and the effects of silicon content,hydrogen content,anddensity on its hybrid carbon bonding and mechanical properties were investigated.The results show that with thesilicon content increasing,the molecules tend to form a silicon-containing macromolecule,and the types and numberof small molecules decrease,the silicon content improves the mechanical properties by promoting the binding ofcarbon and silicon atoms and inhibiting the formation of end-group sp^(3)CH_(3).Besides,species such as·C2H_(3),·C3H5 and·Si(CH_(3))3 were found during the formation of Si-GDP,which were in good agreement with the thin film depositionexperiment of glow discharge polymer.The hydrogen content is measured as the atomic ratio of hydrogen to carbonand silicon,as the ratio grows,the number of model molecules did not change significantly,the ratio of sp^(3)C andsp^(3)CH_(3)increased,and the hydrogen content decreased the mechanical properties mainly by promoting the formation ofsp^(3)CH_(3).With the density increasing,the number of molecular species in the model did not change much,and theproportion of sp^(2)C in the model was significantly increased,while the proportion of sp^(3)C was slightly increased,themechanical properties of Si-doped hydrogenated amorphous carbon were mainly improved by increasing theproportion of sp^(2)C.This study provides an example for constructing Si-GDP by ReaxFF MD,and may provide a newmethod and reference for evaluating the structure and mechanical properties of Si-GDP.

关 键 词：反应分子动力学模拟 辉光放电聚合物 力学性能 硅掺杂 

分 类 号：O484[理学—固体物理]