The solution mixing is the simple general-purpose method for preparing graphene-based polymer composites. Generally, graphene or graphene derivatives are mixed with polymers via mechanical mixing and/or ultrasonic dispersion, and subsequent removal of the solvent. For instance, Huang Y et al. [7] reported a novel self-healing material fabricated with few-layer graphene (FG) and thermoplastic polyurethane (TPU) by solution mixing. Besides its enhanced mechanical property, the FG-TPU self-healing material can be healed by infrared (IR) light, electricity and electromagnetic wave with excellent healing efficiencies higher than 98% (Fig. 2a). Graphene derivatives refer to the functionalized graphene grafted by some groups, especially containing oxygen groups [86,87], which have better compatibility with polymers due to the presence of oxygen functional groups. Beckert F et al. [64] fabricated the PG-DAT/PG-CA films hybridized with thermally reduced graphene oxide (TRGO) nanosheets, allowing localized heating via a NIR laser (808 nm) to break the hydrogen bonds, thus allowing molecular motion and relaxation. Herein, TRGO is a partially reduced form of graphene oxide, whose degree of reduction relies on the temperature in reduction process. Hence, TRGO not only has better conductivity, and light absorption capability, but also maintains well water-dispersible. Moreover, Qu L et al. [48] synthesized 1D, 2D, 3D self-repairing functional architectures using graphene oxide triggered by moisture (Fig. 2b, c, d). Thereinto, GO was prepared by oxidation of natural graphite powder using the modified Hummer's method [88]. GO foams were prepared by freeze-drying of as-synthesized GO dispersions. GO films were fabricated by vacuum filtration of as-synthesized aqueous GO dispersions. GO fibers were synthesized by directly wet-spinning of GO suspensions. Fig. 2e portrayed the self-healing mechanism that the GO sheets within fracture surfaces were wetted and swelled because of adsorbing water leading to partial disruption of the hydrogen-bonding interactions between GO sheets. Physically fitting the broken GO blocks together at their wetted fracture surfaces, the GO sheets at interface contact closely with each other caused by the interdiffusion of GO sheets and the capillary force.