The active macromonomer,methoxy polyethylene glycol methacrylate-1200(MPEGMA 1200),used for polycarboxylate high performance water-reducer,was synthesized by direct esterification taking methacrylic acid(MAA) and methoxy polyethylene glycol-1200(MPEG 1200) as raw materials.Through the orthogonal experiments,comprehensive evaluation of mole ratio of MAA to MPEG,dosage of catalyst,polymerization inhibitor and water-carrying agent,reaction temperature and time on esterification were investigated with the ester...