The macromer,methoxy polyethylene glycol methacrylate(MPEGMA),used for polycarboxylate based superplasticizer was prepared by esterification of methacrylic acid(MAA) and methoxy polyethylene glycol(MPEG).The effects of mole ratio of MAA to MPEG(n(MAA)/n(MPEG)),amount of catalyst and inhibitor,esterification temperature and time on esterification were investigated with the esterification rate as measurement index.The result shows that the optimal condition of esterification includes:(n(MAA))/n(MPEG) is 2.5,t...