通过熔融共混法制备了马来酸酐接枝线型低密度聚乙烯/石墨烯（LLDPE-g-MAH/G）纳米复合材料，探讨不同石墨烯含量对LLDPE-g-MAH/G纳米复合材料结晶行为、流变性能及力学性能的影响。结果表明：随着石墨烯含量的增加，复合材料的结晶度、长周期逐渐增加，储能模量、损耗模量和复数黏度呈现先增加而后趋于平缓的趋势，拉伸强度和断裂伸长率均随石墨烯含量的增加呈先升后降的趋势。当石墨烯含量为0.5%时，纳米复合材料的力学性能最佳，拉伸强度和断裂伸长率分别达到26.8 MPa、998%。当石墨烯含量为0.5%时，拉伸后纳米复合材料中聚乙烯晶体和石墨烯同时沿拉伸方向发生取向，使纳米复合材料中的原始晶体受损破碎，晶体尺寸减小，熔点降低。拉伸后纳米复合材料沿拉伸方向的导热系数是拉伸前的3.6倍，导热性能大幅度提升。

Maleic anhydride grafted linear low density polyethylene/graphene (LLDPE-g-MAH/G) nanocomposites were prepared by melt blending. The effects of different graphene content on the crystallization behavior, rheological properties and mechanical properties of LLDPE-g-MAH/G nanocomposites were investigated. The results show that with the increase of graphene content, the crystallinity and long period of the composites increase gradually, the storage modulus, loss modulus and complex viscosity increase first and then tend to be gentle, and the tensile strength and elongation at break increase first and then decrease with the increase of graphene content. When the graphene content is 0.5%, the mechanical properties of the nanocomposites are the best, and the tensile strength and elongation at break reach 26.8 MPa and 998%, respectively. When the graphene content is 0.5%, the polyethylene crystal and graphene in the stretched nanocomposites are oriented along the stretching direction at the same time, so that the original crystal in the nanocomposites is damaged and broken, the crystal size is reduced, and the melting point is reduced. The thermal conductivity of the nanocomposites along the tensile direction after stretching is 3.6 times that before stretching, and the thermal conductivity is greatly improved.