减水保坍型聚羧酸减水剂的合成及性能研究  

Synthesis and Properties of Water-Reducing and Slump-Protecting Polycarboxylate Superplasticizer

作　　者：董建统 刘志勇[1] 胡忠帅 朱丹丹 丁怡 张伟强 来福琨 DONG Jiantong;LIU Zhiyong;HU Zhongshuai;ZHU Dandan;DING Yi;ZHANG Weiqiang;LAI Fukun(College of Civil Engineering,Yantai University,Yantai 264003,China)

机构地区：[1]烟台大学土木工程学院,烟台264003

出　　处：《硅酸盐通报》2024年第1期52-60,共9页Bulletin of the Chinese Ceramic Society

摘　　要：以4-羟丁基乙烯基聚氧乙烯醚(VPEG)大单体、丙烯酸(AA)为主要原料,引入保坍单体丙烯酸羟乙酯(HEA),以巯基丙酸(MPA)为链转移剂,在H_(2)O_(2)/L-抗坏血酸(V_(C))氧化还原引发体系下,通过自由基聚合制备出减水保坍型聚羧酸减水剂(V-HEA)。通过红外光谱、凝胶色谱测试对合成的V-HEA进行分子结构表征,并与市售保坍型聚羧酸减水剂(HPWR-S)进行水化热与混凝土性能对比分析。结果表明,V-HEA的最佳合成工艺参数为酸醚比4.4,酯醚比2.5,引发剂、硫酸亚铁和链转移剂掺量分别占大单体质量的0.76%、0.10%和0.74%。掺入硫酸亚铁可提高单体的转化率,且V-HEA的数均分子量为17650,重均分子量为42713,单体转化率高达95.03%。掺入V-HEA时混凝土的水化峰值温度较掺入HPWR-S时延迟4 h 24 min,且第二水化速率峰出现时间延迟约4 h,更加延缓水泥的水化。掺入V-HEA的混凝土2 h坍落度仅损失5.8%,且混凝土强度与掺入HPWR-S产品相当,V-HEA具有较好的应用前景。The water-reducing and slump-protecting polycarboxylate superplasticizer(V-HEA)was prepared by free-radical polymerization with 4-hydroxybutyl vinyl polyoxyethylene ether(VPEG)macromonomer and acrylic acid(AA)as the main raw materials by adding the slump-preserving monomer hydroxyethyl acrylate(HEA),and mercapto-propionic acid(MPA)as chain transferr agent under the H_(2)O_(2)/L-vitamin C(V_(C))oxidation-reductioninitiator system.The synthesized V-HEA was characterized by infrared spectroscopy,gel chromatography testing,and it was subjected to hydration heat analysis and concrete performance comparison analysis with commercially available slump-preserving polycarboxylate superplasticizer(HPWR-S).The results show that the optimal synthesis process parameters of V-HEA are acid-ether ratio of 4.4,esterether ratio of 2.5,and the dosage of initiator,ferrous sulfate and chain transfer agent accounted for 0.76%,0.10% and 0.74% of the mass of the macromonomer,respectively.The incorporation of ferrous sulfate could improve the conversion rate of monomers,and the number average molecular weight of V-HEA is 17650,the weight average molecular weight is 42713,and the conversion rate of monomers is as high as 95.03%.The peak temperature of hydration reaches by the incorporation of V-HEA is delayed by 4 h 24 min compared with HPWR-S,and the occurrence time of the second hydration rate peak is delayed by about 4 h,which further delays the hydration of cement.In comparison test of concrete performance,the 2 h slump only decreases by 5.8%with the addition of V-HEA,and the strength of concrete is comparable to that of HPWR-S products,so V-HEA has good application prospects.

关 键 词：聚羧酸减水剂 VPEG大单体 自由基聚合 保坍型 分子结构表征 水化热分析 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]