N-methoxypolyethylene glycols-N,-carbamyl maleimide and preparation method thereof

The invention relates to N-methoxypolyethylene glycols-N,-carbamyl maleimide and a preparation method thereof. The preparation method comprises the following steps: using thionyl chloride and methoxypolyethylene glycols as reactants, and synthetizing chlorinated methoxypolyethylene glycols in a toluene solution; using carbonamides and maleic amide as reactants, synthetizing N-carbamyl maleimide under the action of a catalyst, and through an addition reaction, grafting the chlorinated methoxypolyethylene glycols to the N-carbamyl maleimide so as to obtain a reactive monomer of a polycarboxylate-type water reducing agent. The preparation method has the advantages of mild reaction conditions, short reaction time, high yield and the like.