▎ 摘　　要

NOVELTY - Preparing polycarboxylic acid-modified oxidized graphene composite comprises (i) carrying out hydrolysis reaction of alkyl hydroxy monomer (III), then reacting with graphene oxide, where A group grafted on the surface of the graphene oxide, (ii) carrying out radical polymerization of modified graphene prepared in the step (i), alkene-carboxy monomer (I) and (II), compounding polycarboxylic acid molecule between the layers of the graphene oxide sheet to obtain final product. USE - The polycarboxylic acid-modified oxidized graphene composite is useful as water reducing agent in the hydration process of cement (the amount of the complex is 0.01-5 wt.% the weight of the gelling material) (claimed). ADVANTAGE - The polycarboxylic acid-modified oxidized graphene composite improves the workability of cement slurry, increasing the toughening effect, and improves the flexural and compressive strength of cement-based materials, and improve the early flexural strength. DETAILED DESCRIPTION - Preparing polycarboxylic acid-modified oxidized graphene composite comprises (i) carrying out hydrolysis reaction of alkyl hydroxy monomer of formula (III), then reacting with graphene oxide, where A group grafted on the surface of the graphene oxide, (ii) carrying out radical polymerization of modified graphene prepared in the step (i), alkene-carboxy monomer of formula (I) and (II), compounding polycarboxylic acid molecule between the layers of the graphene oxide sheet to obtain final product. R1 = H or group containing an unsaturated carbon-carbon bond; n = 200-500; R2 = H or methyl; R3 = H or -C(=O)OM; M = alkali metal ion, ammonium ion or organic amine group; X = Cl, methoxy, -OC2H5, OC2H4OCH3, OSiMe3 or -OAc; and A = alkenyl group. An INDEPENDENT CLAIM is also included for polycarboxylic acid-modified oxidized graphene composite obtained by above method.