采用过量的对甲苯磺酰异氰酸酯(TI)处理氧化石墨烯(GO),经化学还原后制备了一种具有优异分散性能的功能化石墨烯TI-RGO。利用红外光谱、X射线光电子能谱、原子力显微镜、透射电镜、扫描电镜和X射线衍射仪等手段对TI-RGO的结构、形貌和分散性进行了表征。结果表明:TI通过异氰酸酯基团(—NCO)与GO的羟基(—OH)等反应形成的共价键连接在石墨烯表面,对其进行有机化修饰,有效地改善了石墨烯在溶剂和聚氨酯(PU)中的分散性。研究发现,TI-RGO可显著地增强PU的拉伸强度,当TI-RGO在PU中质量含量为1.0%时,断裂强度和杨氏模量分别提高了85%和132%,分别达到43.2MPa和5.2MPa。
A functional graphene TI-RGO with good dispersion was prepared by the reaction of p-toluenesulfonyl isocyanate (TI) with graphene oxide (GO) and then reduced by hydrazine hydrate.Infrared spectroscopy(FT-IR),X-ray photoelectron spectroscopy (XPS),atomic force microscope(AFM),transmission electron microscope(TEM),scanning electron microscope(SEM) and X-ray diffractometer (XRD) were used to characterize its structure,morphology and dispersion.The results showed that the isocyanate groups(—NCO) of TI reacted with the hydroxyl(—OH) and carboxyl(—COOH) of GO and connected to the surface of graphene by covalent bond,which made it had good dispersity and can be fully stripped and dispersed in polar solvents.It was found that TI-RGO had good dispersion in polyurethane (PU),and can significantly enhance the mechanical strength of PU.The tensile strength and Young's modulus of the TI-RGO/PU were increased by 85% and 132%,reached up to 43.2MPa and 5.2MPa,respectively,with the addition of 1.0wt% TI-RGO.
[1] Singh V,Joung D,Zhai L,et al.Graphene based materials:past,present and future[J].Prog Mater Sci,2011,56:1178-1271.
[2] Lan Y,Liu H,Cao X H,et al.Electricallyc onductive thermoplastic polyurethane/polypropylene nanocomposites with selectively distributed graphene[J].Polymer,2016,97(5):11-19.
[3] Du X,Skachko I,Barker A,et al.Approaching ballistic transport in suspended graphene[J].Nat Nanotechnol,2008,3(8):491-495.
[4] Ding Y J,Zhu J Q,Wang C H,et al.Multifunctional three-dimensional graphene nanoribbons composite sponge[J].Carbon,104(2016):133-140.
[5] Bandyopadhyay P,Park W B,Layek R K,et al.Hexylamine functionalized reduced graphene oxide/polyurethane nanocomposite-coated nylon for enhanced hydrogen gas barrier film[J].Journal of Membrane Science,2016,500(15):106-114.
[6] Santosh K Y,Jae W C.Functionalized graphene nanoplatelets for enhanced mechanical and thermal properties of polyurethane nanocomposites[J].Appl Surf Sci,2013,266:360-367.
[7] Kim J,Yim B S,Kim J.The effects of functionalized graphene nanosheets on the thermal and mechanical properties of epoxy composites for anisotropic conductive adhesives[J].Microelectronics Reliability,2012,52:595-602.
[8] 于运歌,欧耀明,沈国康,等.石墨烯-聚氨酯复合材料的研究进展[J].聚氨酯工业,2018,33(3):1-4.
[9] Shan C,Yang H,Han D,et al.Water soluble graphene covalently functionalized by biocompatible poly-l-lysine[J].Langmuir,2009,25(20):12030-12033.
[10] Nguyen D A,Lee Y R,Raghu A V,et al.Morphological and physical properties of a thermoplastic polyurethane reinforced with functionalized graphene sheet[J].Polym Int,2009,58(4):412-417.
[11] Sadasivuni K K,Ponnamma D,Kumar B,et al.Dielectric properties of modified graphene oxide filled polyurethane nanoomposites and its correlation with rheologgy[J].Composites Science and Technology,2014(4):18-25.
[12] Wu S L,Shi T J,Zhang L Y.Preparation and properties of amine-functionalized reduced graphene oxide/waterborne polyurethane nanocomposites[J].High Performance Polymers,2016,28(4):453-465.
[13] 严红革,曾跃辉,陈宪宏.石墨烯/聚氨酯纳米复合材料的制备及力学性能研究[J].湖南大学学报(自然科学版),2018,45(6):45-50.
[14] Wang G,Hu Y,Song L,et al.In-situ polymerization of graphene nanosheets and polyurethane with enhanced mechanical and thermal properties[J].J Mater Chem,2011,21:4222-4227.
基金资助
国家自然科学基金(21571047)
PDF
(4355KB)
