摘要
以马来酸酐(MA)和聚乙二醇(PEG)为原料酯化合成大单体马来酸聚乙二醇酯(MAPEG),并测定酯化率,用IR表征酯化物的结构。以马来酸聚乙二醇单酯(MAPEG)、烯丙基磺酸钠(SAS)和丙烯酰胺(AM)为原料通过共聚反应制得MAPEG-SAS-AM三元共聚物高效减水剂。讨论了共聚反应中影响合成减水剂性能的因素,并用GPC表征了减水剂的相对分子量及其分布。通过SEM分析了水泥石的微观结构。结果显示,当n(MAPEG)∶n(SAS)∶n(AM)=1.0∶1.5∶1.5,聚合反应温度为75℃,聚合反应时间为8 h,引发剂用量为单体总质量的9%,PEG相对分子质量为1 000时,合成减水剂的综合性能良好。当其掺量为1.0%时,水泥净浆初始流动度达313 mm。GPC分析显示减水剂平均分子量Mn=6 754,分散系数Mw/Mn=2.156,SEM分析结果显示减水剂使水泥石大孔减少,结晶生长更密实。
The macromolecular monomer（PEGMA） was prepared firstly by maleic anhydride（MA） and polyethylene glycol（PEG）,and the yield of esterification was determinated.The structure of esterification was characterized by IR.The polycarboxylate terpolymer superplasticizer MAPEG-SAS-AM was prepared by copolymerization of esterification intermediate（PEGMA）,sodium allylsulphonate（SAS）,and acrylamide（AM）.The copolymerization effects on performance of superplasticizer were researched.Relative molecule mass and its distribution of superplasticizer was measured by GPC,and the microstructure of cement was characterized by SEM.The results showed that when the molar ratio of MAPEG to SAS to AM was 1.0：1.5：1.5,the polymerization reaction temperature was 85 ℃,the polymerization reaction time was 8 h,the dosage of initiator was 9% of total monomer mass and the relative molecule of PEG mass was 1 000,the superplasticizer prepared under this condition would exhibit good performance.The original fluidity of cement grout could reach 305mm with 1.0% percentage mass content of this superplasticizer.GPC showed that the mean molecular weight Mn and polydispersity Mw/Mn of the superplasticizer was 6 754 and 2.156.SEM showed the amount of macropors of cement added with the polymerization reducing,and the crystals grow more dense.
出处
《混凝土》
CAS
CSCD
北大核心
2012年第10期84-88,共5页
Concrete
基金
国家自然科学基金(21076121)
关键词
高效减水剂
净浆流动度
三元共聚物
马来酸酐
superplasticizer
fluidity of cement grout
terpolymer
maleic anhydride
