首先以二乙醇胺和丙烯酸甲酯为原料,制备了前驱单体N,N-二羟乙基-3-胺基丙烯酸甲酯,其次以三羟甲基丙烷为反应中心核,采用有核准一步法合成端羟基超支化聚(胺-酯)(HPAE);然后利用丁二酸酐和聚氧乙烯烷基醚合成小分子减缩剂SRA;最后利用小分子减缩剂SRA对HPAE进行端基改性,得到了超支化减缩剂HPAE-SRA.通过IR、羟值、减缩性能等表征测试表明:小分子减缩剂SRA成功地接枝到了HPAE分子表面;HPAE-SRA可以大幅降低水泥胶砂浆的收缩性能,3 d和28 d的砂浆减缩率分别为48.8%和36.6%;减缩剂的掺入对水泥胶砂的抗压强度影响较小,对抗折强度有利.%Hyper branched polymer (amine-ester)with terminal alcohol group(HPAE) was synthesized by polycondensation of N,N-diethyol-3-amine-methylpropionate(prepared by Michael addition reaction of methyl acrylate with diethanolamine) as precursor monomer with trimethylol propane as the core moiety,proceeding in pseude-one-step procedure. The shrinkage reducing agent SRA was synthesized by the succinic and polyoxyethylene alkyl ether. Finally,it was modified by SRA to obtain HPAE-SRA hyper branched shrinkage reducing admixture. The obtained polymer was characterized by means of IR,hydroxyl value and shrinkage performance tests,which indicated that micro molecule shrinkage reducing admixture grafted to HPAE successfully. It showed that HPAE-SRA can greatly reduce the shrinkage performance of the cement mortar,at the age of 3 days and 28 days,the shrinkage rate were 48.8% and 36.6% respectively,it had a little negative effect on the cement mortar compressive strength,and had favor-able effect on the flexural strength.
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