摘要
采用熔融法酯化制备具有减缩性能的功能分子,通过聚合反应将减缩基团接枝到主链上,得到减缩增强型聚羧酸减水剂;探讨反应温度、反应时间、酸醇比、催化剂等对产物酯化率的影响,并比较不同提纯方法对酯化物纯度的影响。结果表明:反应温度为130℃,反应时间为4.5 h,酸醇比为3∶1,催化剂用量为0时,酯化反应产物的酯化率较高;采用减压抽滤法提纯酯化物效果更佳;且0.3%掺量的减缩型聚羧酸减水剂(RSPC)28 d减缩率与2%掺量的减缩剂相当。
A multifunctional shrinkage-reducing polycarboxylate superplasticizer was synthesized by introducing a shrinkage-reducing group,which was prepared by melt esterification.The effects of reaction temperature and time, the ration of reactants, catalyst on esterifica-tion rate were investigated.And then, the two different methods of purifcation for esterifieation were contrasted.The result shows that the reaction temperature is 130 ℃, the reaction time is 4.5 hours, the ration of MAD to DGBE is 3：1, the dosage of catalyst is 0, negative-pres-sure filtration is better for purity of ester.And the shrinkage reducing ratio of modified RSPC with 0.3% content is be equivalent to SRA with 2% content.
出处
《混凝土》
CAS
CSCD
北大核心
2013年第11期108-111,共4页
Concrete
关键词
聚羧酸减水剂
酯化物
提纯方法
减缩性能
purification method
ester
reducing performance
polycarboxylate superplasticizer
