一种缓释保坍聚羧酸减水剂的制备及性能研究  

Research on the preparation and performance of a slow-release slump retaining polycarboxylate superplasticizer

作　　者：李修固 王立艳[1] 戚龙娟 盖广清[1] LI Xiu-gu;WANG Li-yan;QI Long-juan;GAI Guang-qing(Jilin building energy saving technology Engineering Laboratory,School of Materials Science and Engineering,Jilin Jianzhu University,Changchun 130118 China)

机构地区：[1]吉林建筑大学材料科学与工程学院吉林省建筑节能技术工程实验室,吉林长春130118

出　　处：《化学研究与应用》2022年第9期2186-2192,共7页Chemical Research and Application

基　　金：吉林省科技发展计划重点研发项目(20210203098SF)资助;住房与城乡建设部研究开发项目(2019-K-050)资助;吉林省产业技术研究与开发项目(2019C059)资助;吉林省科技发展计划项目(20180520217JH)资助。

摘　　要：以乙二醇单乙烯基聚乙二醇醚(EPEG)、丙烯酸(AA)、丙烯酸羟乙酯(HEA)为单体,在氧化还原引发体系下,通过自由基共聚合成一种性能优良的缓释保坍型聚羧酸减水剂。研究了酸醚比、酯醚比、链转移剂用量和引发剂用量对减水剂分散性能的影响。结果研究表明,新型聚羧酸减水剂的最优合成工艺为n(EPEG):n(AA):n(HEA)=1:2.4:1.8,链转移剂占大单体质量的0.65%,引发剂为大单体质量的0.3%;利用热重分析仪、XRD以及SEM电镜微观结构分析,表明减水剂延缓了水泥水化具有缓释保坍作用。合成的减水剂在水灰比0.29,折固掺量0.2%时,水泥净浆的流动度在2h内仍可达到302.5mm;掺减水剂后胶砂抗压抗折强度分别提高了20%和16.8%。混凝土试验结果表明掺入自制减水剂的新拌混凝土和易性优良,3h内坍落度损失仅为4.88%。A high slump retention polycarboxylate superplasticizer was synthesized from ethylene glycol monovinyl polyethylene glycol ether,acrylic acid and hydroxyethyl acrylate by radical polymerization in the redox initiation system.The effects of acid ether ratio,ester ether ratio,the amount of chain transfer agent and initiator on the dispersion performance of water reducer were studied.The results show that the optimal synthesis process of the new polycarboxylate superplasticizer is n(EPEG):n(AA):n(HEA)=1:2.4:1.8,the chain transfer agent accounts for 0.65%of the mass of macromonomer,and the initiator is 0.3%of the mass of macromonomer;the microstructure analysis by thermogravimetry,XRD and SEM showed that the water reducing agent delayed the hydration of cement and had the effect of slow-release and slump retention.When the water cement ratio is 0.29 and the solid content is 0.2%,the fluidity of cement paste can still reach 302.5 mm within 2 h,the compressive and flexural strength of cement mortar increased by 20%and 16.8%after adding water reducing agent.The concrete test results show that the workability of fresh concrete mixed with self-made water reducing agent is excellent,and the slump loss within 3 h is 4.88%.

关 键 词：乙二醇单乙烯基聚乙二醇醚 聚羧酸减水剂 丙烯酸羟乙酯 缓释保坍 

分 类 号：O633.11[理学—高分子化学]