实验与分子模拟法结合探究防老剂对天然橡胶热氧老化的防护机理  

Protection Mechanism of Antioxidant for Thermo-Oxidative Ageing of Natural Rubber with Combination of Experimental and Molecular Dynamics Simulation

作　　者：李强国[1] 陈新 张卓 郑玮[1] 刘丽园 吴丝竹[1] 

机构地区：[1]北京化工大学北京市先进弹性体工程技术研究中心,北京100029 [2]全球能源互联网研究院先进输电技术国家重点实验室,北京102209

出　　处：《高分子材料科学与工程》2018年第1期106-111,118,共7页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51473012);国家科技发展计划(2014BAE14B01)

摘　　要：研究了添加防老剂N-(1,3-二甲基丁基)-N'-苯基对苯二胺(防老剂4020)或N-苯基-2-萘胺(防老剂D)/天然橡胶(NR)复合材料的抗热氧老化性能。使用衰减全反射傅里叶变换红外光谱分别对纯NR、添加防老剂4020或添加防老剂D的复合材料在热氧老化箱内氧化不同天数后的样品进行结构剖析,同时对其力学性能参数如拉伸强度和断裂伸长率的变化进行测定,发现防老剂4020对NR的热氧老化防护作用优于防老剂D;采用全原子分子模拟法分别计算了防老剂4020、防老剂D以及NR的溶解度参数(CED),防老剂4020和防老剂D在NR中的均方位移(MSD),防老剂4020或防老剂D与NR高分子链的结合能。从微观结构角度论证了防老剂4020优于防老剂D的机理及原因,表明使用全原子分子模拟法对橡胶复合材料防老剂的选择有一定的指导意义。The thermo-oxidative ageing resistance of natural rubber（NR） which is mixed with the antioxidant N-1,3-dimethylbutyl-N＇-phenyl-p-phenylenediamine（4020） or antioxidant N-phenyl-2-naphthylamine（D） was studied with combination of experimental and molecular dynamics simulation.In experiment,the variations of structural components of NR mixed with antioxidant 4020 or antioxidant D,which was oxidized respectively for 0 d,1 d,2 d,4 d,7 d at 80 ℃in the thermo-oxidative ageing oven,were analyzed by ATR-FT-IR;the variations of tensile strength and elongation at break were measured.The results of experiment conclude that the antioxidant 4020 has a better protection effects for NR.Then,in molecular dynamics simulation,the solubility parameter（SP） of antioxidant 4020,antioxidant D and NR,the mean square displacement（MSD） of antioxidant 4020 and antioxidant D in NR and the binding energy of antioxidant 4020 or antioxidant D with the NR were calculated.The calculation results of SP show that the antioxidant 4020 has a better solubility with NR;the results of MSD indicate that the antioxidant 4020 has a poor ability of migration than antioxidant D,inferring the antioxidant 4020 can stay in NR for longer time when they are mixed;at last,the binding energy of the antioxidant 4020 with NR is greater than antioxidant D with NR.The calculation results all declare that the antioxidant 4020 has a better protection effects to NR from the micro-perspective,which is in accord with the experimental results.It shows that the atomistic molecular dynamics simulation has important directive significance in selecting antioxidants.

关 键 词：天然橡胶 全原子分子模拟 溶解度参数 均方位移 结合能 

分 类 号：TQ332.5[化学工程—橡胶工业]