▎ 摘　　要

NOVELTY - Method for preparing graphene wave-absorbing patch by (i) adding boron-containing dopant to graphite oxide solution, hydrothermally heating and performing constant heat reaction to obtain black gel-like liquid, (ii) cooling the black gel-like liquid to room temperature, washing and filtering with deionized water and freeze-drying, (iii) adding absolute ethanol to boron-doped graphene powder to obtain dispersion, and centrifuging to obtain a supernatant, (iv) adding supernatant and tetrahydrofuran to polylactic acid, stirring and dissolving the mixture to obtain a mixed solution, adding plasticizer to the mixed solution, mixing to obtain polylactic acid-boron-doped graphene mixed solution, and (v) heating polylactic acid-boron-doped graphene mixed solution in stainless steel reactor to obtain polylactic acid-boron-doped graphene casting film solution, taking out and pouring the casting film solution into steel sheet or petri dish and natural drying. USE - Method for preparing graphene wave-absorbing patch. ADVANTAGE - The method is economical, simple and consumes less energy. DETAILED DESCRIPTION - Method for preparing graphene wave-absorbing patch by (i) adding boron-containing dopant to graphite oxide solution in a ratio of (1-3):(100-200) g/ml, hydrothermally heating at 120 degrees C, and continuously performing constant heat reaction for 1-3 hours to obtain black gel-like liquid, (ii) cooling the black gel-like liquid to room temperature, washing and filtering several times with deionized water and freeze-drying to obtain black boron-doped graphene powder, (iii) adding absolute ethanol to boron-doped graphene powder to obtain dispersion having a concentration of 2-5 mg/ml, and centrifuging to obtain a supernatant, (iv) sequentially adding supernatant and tetrahydrofuran to polylactic acid, stirring and dissolving the mixture to room temperature to obtain a mixed solution, adding 5-30 %mass plasticizer to the mixed solution, uniformly mixing to obtain polylactic acid-boron-doped graphene mixed solution, where the ratio of polylactic acid to supernatant is 1:20 g/ml, and polylactic acid to tetrahydrofuran is 1:20 g/ml and (v) hydrothermally heating polylactic acid-boron-doped graphene mixed solution at 100 degrees C stainless steel reactor for 30 minutes to obtain polylactic acid-boron-doped graphene casting film solution, quickly taking out and pouring the casting film solution into steel sheet or petri dish and natural drying to obtain the product.