摘要
利用甲基丙烯酸、聚乙二醇单甲醚直接酯化合成甲氧基聚氧化乙烯甲基丙烯酸酯,采用预处理的方法制备了甲基丙烯酸高效阻聚剂,同时研究了相对分子质量、反应温度、反应时间对酯化反应的影响规律。结果表明:预处理制备的TN酚醌混合阻聚剂对甲基丙烯酸具有良好阻聚效果,掺量为0.75%时,120℃反应20h无明显聚合;140℃时,聚乙二醇单甲醚开始分解,—OH被氧化,产生了C=O;120℃时TN催化剂与MPEG混合物能够稳定存在,基本无副反应发生,该体系酯化率可达到99%;MPEG相对分子质量影响反应速度,酯化反应1～4h酯化率随相对分子质量的增加而降低;当反应4h时,转化率已达80%。之后反应速度减慢,酯化率随MPEG相对分子质量的变化较小。
Methoxy polyethylene glycol monomethacrylate eaters are synthesized from methacrylic acid （MAA） and methoxy polyethylene glycol （MPEG）. A composite TN inhibitor for methacrylic acid is prepared beforehand using pretreatment method. Effect of MPEG molecular weight, temperature and reaction time on the esterification are discussed. The TN inhibitor is proved to have excellent inhibition ability to the polymerization of MAA. With 0.75% of TN, MAA does not visible polymerize at 120℃ for 20 h. While, MPEG starts to decompose at 140 ℃, where the -OH group is oxidized to C=O in some extent. The mixture of TN and MPEG is stable at 120℃, where the esterification with MAA can be achieved to 99%. The esterification rate decreases with the increase of MPEG molecular weight at the early 4 h, but there is little effect of MPEG molecular weight after 4 h reaction when the esterification rate is above 80%.
出处
《化工进展》
EI
CAS
CSCD
北大核心
2009年第8期1390-1394,共5页
Chemical Industry and Engineering Progress
基金
中国博士后科学基金项目资助(20070410969)
关键词
聚氧化乙烯
酯化率
预处理
阻聚
polyethylene glycol esterification rate pretreatment method inhibition
