水溶液中可逆加成断裂链转移法制备梯度结构保坍型聚羧酸减水剂  

Preparation of gradient slump retaining polycarboxylic acid water reducer by RAFT aqueous solution polymerization

作　　者：王洪根 石艳[1] 赵斌 惠嘉[3] 方茜亚 燕春福 杨富民 魏道新[3] WANG Honggen;SHI Yan;ZHAO Bin;HUI Jia;FANG Xiya;YAN Chunfu;YANG Fumin;WEI Daoxin(State Key Laboratory of Organic-Inorganic Composites,Beijing University of Chemical Technology,Beijing 100029,China;Beijing Shoufa Tianren Ecological Landscape Co.Ltd.,Beijing 102600,China;China Academy of Transportation Science,Beijing 100029,China;Beijing Tieke Shougang Rail-Tech.Co.Ltd.,Beijing 102206,China)

机构地区：[1]北京化工大学有机无机复合材料国家重点实验室,北京100029 [2]北京市首发天人生态景观有限公司,北京102600 [3]交通运输部科学研究院,北京100029 [4]北京铁科首钢轨道技术股份有限公司,北京102206

出　　处：《新型建筑材料》2023年第9期129-133,共5页New Building Materials

基　　金：石家庄市科学技术研究与发展计划项目(201160144A)。

摘　　要：通过可逆加成-断裂链转移(RAFT)聚合在水溶液中利用半连续单体投料工艺成功合成了一种梯度结构保坍型聚羧酸减水剂(PCEs)。TPEG大单体采用一次性加入、AA和保坍型功能单体HEA采用滴加工艺,用水溶性RAFT试剂BDMAT调控三者的共聚合,所得共聚物的分子质量分布很窄,分布指数在1.26~1.35;大单体的转化率与反应时间呈线性关系,验证该体系为活性聚合体系;TPEG单体转化率随时间呈梯度变化,证明共聚物的序列特征为梯度结构;水泥净浆流动度测试表征了梯度产物的保坍性能。In this paper,a slump retaining PCEs with gradient structure was successfully synthesized by reversible addition-fragmentation chain transfer radical(RAFT)polymerization in aqueous solution using semi continuous monomer feeding process.With TPEG macromonomer employing one-time addition process,AA and slump preserving functional monomer hydroxyethyl acrylate(HEA)adopting dropping process,the copolymerization of the three monomers is controlled by water-soluble RAFT reagent BDMAT.The molecular weight distribution of the obtained copolymers is very narrow,and the distribution index is between 1.26~1.35.The linear relationship between the conversion of macromonomer and reaction time verifies that the system is a living polymerization system.The conversion of TPEG monomer determined by 1H NMR spectra showed a gradient change with reaction time,which proved that the sequence characteristics of the PCEs macromolecules were gradient structure.The fluidity test of cement paste characterizes the slump retention performance of the PCEs with gradient structure.

关 键 词：RAFT聚合 梯度结构 保坍 聚羧酸减水剂 净浆流动度 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]