▎ 摘　　要

NOVELTY - Preparing a modified graphene oxide concrete crack repairing material comprises e.g. oxidizing graphene dispersion and adding water and stirring uniformly, then adding N-hydroxysuccinimide and L-cysteine, and introducing nitrogen gas, acting and stirring, and isolating the product by centrifugation to obtain a slurry-modified graphene oxide having a terminal sulfhydryl group, adding 3-butyn-1-ol, tetrahydrofuran and triethylamine to the reactor, introducing nitrogen gas, and slowly adding 2-bromo-2-methylpropionyl bromide at, stirring and reacting, adding deionized water, stirring, allowing to stand, stratifying, discarding the aqueous phase, to obtain 2-bromo-2-methylpropionic acid 3-butynyl ester, adding cuprous bromide, pentamethyldiethylenetriamine, 3-bromo-2-methylpropanoic acid 3-butynyl ester and hydroxypropyl acrylate, introducing nitrogen gas, stirring, then cooling and reacting, pouring into ethanol to produce a precipitate. USE - The method is useful for preparing a modified graphene oxide concrete crack repairing material. ADVANTAGE - The method: combines a large-size monolithic graphene oxide uniform dispersion liquid into a concrete crack repairing material, and promotes the formation of regular and uniform hydration products, and aggregates to form an intertwined and crosslinked dense structure to achieve the best repair of concrete cracks; introduces functional aqueous-based polymer, optimizes product performance, economical, has simple production and repair process. DETAILED DESCRIPTION - Preparing a modified graphene oxide concrete crack repairing material comprises (i) oxidizing 2-2.5 wt.% of 40-60 pts. wt. graphene dispersion and adding to 90-100 pts. wt. water and stirring uniformly, then adding 0.1-0.3 pts. wt. N-hydroxysuccinimide and 3-4.5 pts. wt. L-cysteine, and introducing nitrogen gas, acting and stirring at 25-30 degrees C for 7-8 hours, and isolating the product by centrifugation to obtain a slurry-modified graphene oxide having a terminal sulfhydryl group, and the mass fraction of modified graphene oxide dispersion is controlled by using 0.6-0.8% deionized water; (ii) adding 10-15 pts. wt. 3-butyn-1-ol, 60-80 pts. wt. tetrahydrofuran and 8-12 pts. wt. triethylamine to the reactor, introducing nitrogen gas, and slowly adding 6.4-7.4 pts. wt. 2-bromo-2-methylpropionyl bromide at 30-40 degrees C for 30-40 minutes, stirring and reacting for 10-15 hours, adding 80-100 pts. wt. deionized water, stirring for 3-5 minutes, allowing to stand for 30-35 minutes, stratifying, discarding the aqueous phase, to obtain 2-bromo-2-methylpropionic acid 3-butynyl ester; (iii) adding 0.05-0.1 pts. wt. cuprous bromide, 0.1-0.2 pts. wt. pentamethyldiethylenetriamine, 17.8-19.6 pts. wt. 3-bromo-2-methylpropanoic acid 3-butynyl ester and 45-55 pts. wt. hydroxypropyl acrylate, introducing nitrogen gas, stirring at 75-85 degrees C for 4-5 hours, then cooling and reacting at 25-30 degrees C, pouring into ethanol to produce a precipitate, filtering and washing in ethanol for many times to obtain modified polyhydroxypropyl acrylate with terminal alkynyl group; (iv) adding 80-100 pts. wt. modified graphene oxide dispersion having a terminal thiol group prepared in the step (i), mixing with 20-30 pts. wt. modified polyhydroxyl acrylate having a terminal alkynyl group prepared in the step (iii), heating at 70-80 degrees C, and adding to 0.8-1.0 pts. wt. triethylamine, heat preserving and reacting for 10-12 hours to obtain a large-size monolithic layer modified graphene oxide dispersion; (v) uniformly mixing 85-90 pts. wt. 42.5 grade ordinary portland cement, 5-10 pts. wt. 42.5 grade sulfoaluminate cement, 5-10 pts. wt. fly ash and 95-100 pts. wt. river sand; (vi) mixing 0.3-0.5 pts. wt. sodium silicate, 0.01-0.03 pts. wt. sodium nitrate, 0.01-0.03 pts. wt. sodium nitrite, 0.2-0.4 pts. wt. potassium aluminum sulfate, and 0.1-0.3 pts. wt. iron sulfate; (v) taking 10-12 pts. wt. large-size monolithic graphene oxide nanosheet layer dispersion prepared in the step (iv), 2-2.5 pts. wt. polycarboxylic acid water reducing agent, and 2-3 pts. wt. aqueous polymerized material, mixing the mixture with 8-10 pts. wt. water and stirring uniformly; and (viii) mixing the products obtained in steps (v), (vi) and (vii) and stirring for 5 minutes. An INDEPENDENT CLAIM is also included for modified graphene oxide concrete crack repairing material, prepared by the preparation method.