Synthesizing and compounding method of polycarboxylate-type high-efficiency water reducing agent

The invention discloses a synthesizing and compounding method of polycarboxylate-type high-efficiency water reducing agent. The synthesizing and compounding method comprises the following steps of: (1), adopting a solution method to prepare an aqueous solution according to a certain molar ratio by using methacrylic acid, acrylic acid and polyethylene glycol as raw materials; adding the aqueous solution to a four-necked flask with a reflux condenser and a mechanical stirrer; adding catalyst and polymerization inhibitor to obtain precursor methoxy polyoxyethylene acrylate macromonomer; (2), heating up to a certain temperature in water bath, dropwise adding a certain concentration of ammonium persulfate aqueous solution within a certain time, continuously reacting for a certain time by keeping the temperature after the dropwise adding is completed; using 30% of NaOH to adjust the pH of the product to 7-8 after cooling to the room temperature to synthesize novel branched polycarboxylate high-performance water reducing agent; (3), obtaining a compounding system of polycarboxylate-type water reducing agent and naphthalene-type water reducing agent by a compounding process.