关键词:马来酸酐;邻苯二甲酸酐;甲氧基聚乙二醇;酯化反应;小分子减水剂
Esterification of Anhydride and Methoxyl Polyethylene Glycol Ether and Water-reducing Performance of Its Product
Abstract: This article studied the reaction conditions of mono-esterification from methoxy polyethylene glycol(MPEG) and anhydride (maleic anhydride , phthalic anhydride ).The effect of the MPEG molecular weight, the amount of catalyst, reaction time ,the temperature and feed ratio on the esterification rate was discussed in details. It is found that conditions such as MPEG molecular weight, the amount of catalyst ,reaction time, feed ratio and temperature is 1300, 2%, 120 min ,1:1.15 and 90℃ respectively, the esterification rate reaches high level. The structure of product is characterized by IR analysis. The kinetics of the reaction is discussed and the activation energy is calculated. The activation energy of the esterification of phthalic anhydride is higher then the activation energy of maleic anhydride. Meanwhile the esterification product show some function as water-reducing agent in cement.
Keywords: Maleic anhydride; Phthalic anhydride; Methoxy polyethylene glycol; Esterification; Small water-reducing agent