采用甲基烯丙基聚氧乙烯醚与己内酯反应制得的大分子单体与丙烯酸共聚,合成侧链疏水改性的聚羧酸减水剂.研究了温度、催化剂、酸醚比、链转移剂和己内酯个数对聚羧酸性能的影响.合适的条件为:n(丙烯酸):n(大单体)=3.5:1,链转移剂3%,催化剂20 mg/kg,温度45 ℃,己内酯个数2.合成的聚羧酸具有良好的稳泡效果,混凝土含气量适中,和易性得到明显改善,后期强度不受影响.%A series of polycarboxylate superplasticizers were synthesized in water solution by radical copolymerization of acrylic acid and ε-caprolactone modified methyl allyl polyoxyethylene ether. The suitable conditions for reaction were thoroughly investigated and found as follows:monomer molar ratio of 3.5:1,chain transfer agent dosage of 3%,catalyst dosage of 20 mg/kg,reaction temperature of 45 ℃,ε-caprolactone addition number of 2. The concrete mixed with resultant polymer possessed a suitable air content,leading to an obvious improvement of concrete workability while the compressive strength was essentially not affected.
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