液氧相容改性环氧树脂体系低温力学性能分子动力学模拟  

Molecular dynamics simulation of low-temperature mechanical properties of liquid oxygen compatible epoxy resins

作　　者：高畅 董旭峰[1] 严佳 徐浩 武湛君[2] GAO Chang;DONG Xufeng;YAN Jia;XU Hao;WU Zhanjun(School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China;School of Aeronautics and Astronautics, Dalian University of Technology, Dalian 116024, China)

机构地区：[1]大连理工大学材料科学与工程学院,辽宁大连116024 [2]大连理工大学航空航天学院,辽宁大连116024

出　　处：《功能材料》2022年第7期7139-7143,7149,共6页Journal of Functional Materials

基　　金：国家重点研发计划项目(2018YFA0702800)。

摘　　要：使用含磷阻燃剂分子对环氧树脂进行化学改性可以提高材料的液氧相容性,但将显著改变环氧树脂固化物的力学性能。利用分子动力学(MD)模拟方法,研究了10-(2,5-二羟基苯基)-10-氢-9-氧杂-10-磷杂菲-10-氧化物(ODOPB)改性环氧树脂的低温力学性能。首先采用两步反应方案来制备改性的环氧热固性交联网络,然后分别给予ReaxFF与Dreiding力场,基于截断键长实现精确有效的键断裂模拟。着重探索了不同磷含量对分子网络结构和材料性能的影响。研究发现,链长分布特征是决定材料力学性能的关键因素。而通过链长调节(CLR),材料在低温下的力学性能可以明显增强。为高性能液氧相容热固性树脂和复合材料的设计和制造提供了有价值的参考,有助于提高复合材料在恶劣工程环境下的耐受性。Chemical modification of epoxy resin with phosphorus containing flame retardant molecules can improve the liquid oxygen compatibility of materials,but will significantly change the mechanical properties of cured epoxy resin.The low temperature mechanical properties of epoxy resin modified by 10-(2,5-dihydroxyphenyl)-10-hydrogen-9-oxa-10-phosphophenanthrene-10-oxide(ODOPB)were studied by molecular dynamics(MD)simulation.Firstly,the modified epoxy thermosetting crosslinking network was prepared by two-step reaction scheme,and then ReaxFF and dreiding force fields were used,respectively,to realize accurate and efficient bond scission simulation based on calibrated truncated bond length.The effects of different P weight content on molecular network structure and material properties were explored.It is found that the chain length distribution is the key factor to determine the mechanical properties of materials.The mechanical properties of the materials at low temperature can be significantly enhanced by chain length regulation(CLR).This study provides valuable insight for the design and manufacture of high-performance liquid oxygen compatible thermosetting resin and composites,and facilitates to improve the tolerance of composites in harsh engineering environment.

关 键 词：树脂基复合材料 改性环氧树脂 分子动力学 液氧相容性 低温力学性能 

分 类 号：O631.2[理学—高分子化学] U214.02[理学—化学]