含酰胺基团早强型聚羧酸减水剂的制备及性能研究

Study on preparation and property of early strength polycarboxylate superplasticizer containing acylamide group

以异戊烯醇聚氧乙烯醚(TPEG)和丙烯酸(AA)为主要聚合单体,选用丙烯酰胺(AM)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)和N-羟甲基丙烯酰胺(HAM)3种含酰胺基团的早强功能单体,在双氧水-抗坏血酸氧化还原引发体系和巯基乙酸链转移剂条件下制备了早强型聚羧酸减水剂。性能测试及红外光谱分析结果表明:当n(TPEG)∶n(AA)∶n(HAM)=1.0∶3.6∶0.4时,制备的减水剂早强效果优异,该减水剂折固掺量为0.2%时,与掺普通型聚羧酸减水剂的胶砂强度相比,其1d、3d抗压强度分别提高了15.35%、8.83%;酰胺官能团红外特征峰明显,表明早强型聚羧酸减水剂分子主链上含有酰胺基团。

Taking TPEG and AA as the main polymerization monomers,AM and AMPS and HAM three early-strength functional monomer containing an acylamide group was chosen.The early-strength polycarboxylate superplasticizer was synthesized under the conditions of a hydrogen peroxide-ascorbic acid redox initiation system and a thioglycolic acid chain transfer agent.Performance test and infraved spectra analysis results show that when the monomer molar ratio is n(TPEG)∶n(AA)∶n(HAM)=1.0∶3.6∶0.4,the early strength effect of the water reducing agent was outstanding.The compressive strength at 1 d and 3 d of mortar with the early-strength polycarboxylate superplasticizer increased by 15.35%and 8.83%compares with ordinary polycarboxylate superplasticizer when the addition of the early-strength polycarboxylate superplasticizer is 0.2%.The infrared characteristic peak of the amide functional group is obvious,indicating that the early strength polycarboxylate superplasticizer contains an amide group in the main chain.