无烟煤的微波辐照-固相力化学石墨烯化及与天然橡胶的纳米复合

Graphenization of anthracite and nanocomposite with nature rubber through microwave irradiation-solid state mechanochemistry strategy

将无烟煤与路易斯酸催化剂CuCl_(2)混合均匀后置于微波场-固相剪切力场交替作用下进行固相反应,微波场使煤分子内温度达到煤基石墨烯化的反应温度,路易斯酸催化剂在高温环境下使煤分子进行烷基脱除反应,固相力化学反应器提供强大的剪切力场重复粉碎剥离,实现了太西无烟煤的直接石墨烯化,进而在固相剪切碾磨中实现了煤基石墨烯与天然橡胶(NR)的纳米级复合,成功制备出抗静电煤基石墨烯/天然橡胶纳米复合材料。通过工业分析、元素分析、扫描电子显微镜、透射电子显微镜、X射线衍射、拉曼光谱和原子力显微镜等手段分阶段表征了所制备纳米复合材料的结构与性能。结果表明,在氯化铜催化-固相剪切碾磨-微波辐照的共同作用下,可以实现太西无烟煤的粉碎、剥离、脱氧、脱烃、脱氢、芳香稠环,进而向石墨烯化方向发展,最终得到了3.5 nm厚度2D形貌的“煤基石墨烯(CB-GE)”;CB-GE可以实现对天然橡胶的增强和导静电功能化,当CB-GE质量分数为20%时,CB-GE/NR纳米复合材料的拉伸强度、断裂伸长率和电导率分别达到22.36 MPa、278.8%和9.8×10^(-4)S/cm,与天然橡胶材料相比分别提高314.1%、40.52%和9个数量级,当CB-GE质量分数为4%时即可达到抗静电的要求。这表明所制备的CB-GE可以实现对天然橡胶的增强和导静电功能化。氯化铜催化-固相剪切力场-微波场综合作用技术进行无烟煤的石墨烯化过程几乎无“三废”产生,可提升制备煤基石墨烯复合材料的经济性。同时固相力化学复合技术可实现纳米级石墨烯化无烟煤在不同聚合物基体材料中的纳米分散和直接复合,可以得到定向煤基石墨烯/聚合物纳米复合材料。

The anthracite and Lewis acid catalyst CuCl_(2)were mixed evenly and placed under the alternating action of microwave field and solid state shear field for solid state reaction.The microwave field made the internal temperature of the coal reach the reaction temperature of the coal-based graphenization and the Lewis acid catalyst made the alkyl removal reaction of the coal molecules under high temperature environment.Direct graphenization of the Taixi anthracite was achieved by strong shear force field and repeated pulverizing and exfoliating provided by the solid state mechanochemical reactor,and then the nanocomposites of coal-based graphene(CB-GE)and natural rubber(NR)were realized in solid state shear milling,and the CB-GE/NR nanocomposites were successfully prepared.The structure and properties of the nanocomposites were characterized by proximate analysis,elemental analysis,scanning electron microscopy,transission electron microscopy,X-ray diffractometer,Raman spectroscopy and atomic force microscopy.The results show that under the combined action of copper chloride catalysis,solid state shear milling and microwave irradiation,the grinding,stripping,deoxidation,dehydrocarb,dehydrogenation and aromatic condensed rings of the Taixi anthracite can be realized and then developed to the direction of graphenization.Finally,the"coal base graphene(CB-GE)"with 2D morphology of 3.5 nm thickness can be obtained.When the mass fraction of CB-GE is 20%,the tensile strength,elongation at break and electrical conductivity of the CB-GE/NR nanocomposites respectively reach 22.36 MPa,278.8%and 9.8×10^(-4)S/cm.Compared with the natural rubber material,they are increased by 314.1%,40.52%and 9 orders of magnitude,respectively.When the mass fraction of CB-GE is 4%,the antistatic requirements can be reached.The results show that the prepared CB-GE can enhance the natural rubber and carry out electrostatic functionalization.There is almost no waste generated in the process of graphenization of anthracite by copper chloride catalyzation-solid state shear force-microwave field,which can improve the economy of preparing coal-based graphene composites.At the same time,the solid-state mechanochemical compounding technology can realize nano dispersion and direct composite of graphenized anthracite in different polymer matrix materials,and can obtain oriented CB-GE/polymer nanocomposites.