Synthesis method of multifunctional composite super water absorbent resin

The invention discloses a synthesis method of multifunctional composite super water absorbent resin, solving the problems of the traditional super water absorbent resin such as poor water absorbability and electrolyte resistance and single function. The method comprises the following steps: soaking weathered coal with alkali liquor to prepare sodium humate solution; using vinyl monomer and sodiumhumate to perform grafting and crosslinking reaction and generate super water absorbent resin under the protection of N2, wherein the reaction conditions are that dispersant, the mixed solution of cyclohexane and chloroform of which volume ratio is 2:1 and initiator are added, N2 is used for protection, the crosslinking temperature is 55-70 DEG C and the crosslinking time is 1.5-2.5 hours; and extracting and drying the product in a Soxhlet extractor, and then grinding. By using acrylamide, the cost can be reduced and the electrolyte resistance of the product can be increased; and by utilizingthe synergistic effect of