▎ 摘　　要

NOVELTY - Preparing lignin-modified graphene material, comprises e.g. (i) dissolving alkali lignin in sulfuric acid solution, then adding sodium sulfite and copper sulfate, heating and reacting, then allowing to stand, filtering, washing with deionized water until the pH to neutral, concentrating the filtrate and cooling to crystallize to obtain sulfonated lignin, (ii) dispersing sulfonated lignin in concentrated sulfuric acid, magnetically stirring and sonicating, adding slowly potassium permanganate and reacting while maintaining magnetic stirring, heating to 80 degrees C, adding slowly deionized water and hydrogen peroxide solution, then washing with deionized water and drying to obtain hydroxy surface modified lignin, and (iii) adding deionized water to mill tank then stirring, adding zirconia grinding balls, natural flake graphite powder and hydroxy surface modified lignin, and adjusting pH of the solution, rotating the ball mill tank, then stirring, centrifuging, washing, filtering and drying. USE - The lignin-modified graphene material is useful in EVA/rubber composite foam material. ADVANTAGE - The method: is simple, safe and is environmentally friendly. The EVA/rubber composite foam material: utilizes less amount of lignin-modified graphene as additive which improves excellent compatibility with substrate and compatibility between EVA and rubber and improves mechanical properties of composite foam, and is easy to disperse. DETAILED DESCRIPTION - Preparing lignin-modified graphene material, comprises (i) dissolving alkali lignin in sulfuric acid solution, stirring for 30 minutes, then adding sodium sulfite and copper sulfate, heating to 90 degrees C and reacting for 2 hours, then allowing to stand, filtering, washing with deionized water until the pH to neutral, concentrating the filtrate and cooling to crystallize to obtain sulfonated lignin, (ii) dispersing 1 g sulfonated lignin in 10 ml concentrated sulfuric acid, magnetically stirring and sonicating for 30 minutes, adding slowly 3 g potassium permanganate and reacting for 2 hours while maintaining magnetic stirring, heating to 80 degrees C, adding slowly 50 ml deionized water and 10 ml of 5 wt.% hydrogen peroxide solution, then washing with deionized water and drying to obtain hydroxy surface modified lignin, and (iii) adding 150 ml deionized water to 500 ml ball mill tank then stirring, adding zirconia grinding balls of 10 g, 3 g and 0.5 g in quality ratio of 3:30:500, then adding 10- 20 g natural flake graphite powder and 3 g hydroxy surface modified lignin, and adjusting pH of the solution to 10 using aqueous ammonia, rotating the ball mill tank at 220 resolutions/minute, then stirring at 440 resolutions/minute for 48 hours, centrifuging, washing, filtering and drying to obtain final product. INDEPENDENT CLAIMS are also included for: (1) lignin-modified graphene material obtained by above mentioned method; and (2) use of lignin-modified graphene material in ethylene-vinyl acetate/rubber composite foam material, comprising adding lignin-modified graphene material into ethylene-vinyl acetate/rubber (EVA/rubber) composite foam material.