4,4′-二苯基甲烷二异氰酸酯共价功能化氧化石墨烯对聚氨酯的修饰作用

Modification of polyurethane by covalently functionalized graphene oxide with 4,4′-diphenylmethane diisocyanate

通过将氧化石墨烯(GO)与4,4′-二苯基甲烷二异氰酸酯(MDI)共价接枝改性可制备而得大层间距、高反应活性的新型MDI-GO粉体。结果表明,MDI-GO粉体的层间距从0.83 nm扩大至2.43 nm,其在增强聚氨酯弹性体的导热性和机械性能方面效果显著。

Graphene has good prospects in the field of polymer reinforcement,because of its excellent thermal,electrical and mechanical properties.However,due to the strongπ-πstacking interaction between graphene sheets,it is difficult to uniformly disperse in the polymer matrix[1].The covalent grafting of isocyanate onto graphene oxide(GO)is an effective method to expand the graphene interlayer spacing and improve the dispersibility[2].In this paper,GO was modified by 4,4′-diphenylmethane diisocyanate(MDI)to obtain MDI-GO powder with high reactivity and interlayer distance of 2.43 nm,and then MDI-GO/polyurethane(PU)composite was prepared with toluene-2,4-diisocyanate,polytetramethylene ether glycol and MDI-GO as raw materials by in-situ reaction.