【摘要】 以甲基丙烯酸、甲基丙烯磺酸钠、烯丙醇聚乙二醇单甲醚和丙烯酰胺为原料,以过硫酸钠为引发剂,在水溶液中进行自由基聚合反应,合成丙烯酰胺改性聚羧酸减水剂。用傅里叶红外光谱仪分析共聚物分子结构,并用分子凝胶渗透色谱来测定共聚物的分子质量。用水泥净浆流动度来考察聚羧酸减水剂的分散性和分散保持性,并考察其在水泥颗粒上的吸附量。结果表明:合成的共聚物的重均分子质量为43 260;聚羧酸减水剂的折固掺量为0.2%、水灰比为0.29时,水泥的初始净浆流动度达287 mm,60 min净浆流动度为299 mm;合成的改性聚羧酸减水剂具有较好的分散性和分散保持性。根据Langmuir等温吸附模型,水泥对聚羧酸减水剂的饱和吸附量为5.33 mg/g。更多还原

【Abstract】 The polycarboxylic series of water reducer was synthesized by using methacrylic acid,sodium methylallyl sulfonate,allyl alcohol methoxypoly(ethylene glycol)ether and acrylamide as raw materials,sodium persulfate as the initiator for the radical aqueous solution polymerization.FTIR spectrometer were carried out to characterize the structure of the polymers and the molecu lar weight of the polymers was analyzed by gel permeation chromatography(GPC).The dispersity and dispersion retaining ability of the polycarboxylate superplasticizers in cement paste was tested by measuring paste flow,and the absorbance on cement is investigated.The results indicated that when the molecular weight of the polymer measured was 43 260,the initial fluidity of the cement paste could reach 287 mm and the fluidity became 299 mm in 60 minutes with the mass content of this polycarboxylateis 0.2% and water-cement ratio 0.29.The polycarboxylate superplasticizer synthesized had good dispersity and dispersion retaining ability,saturated adsorption of polycarboxylate superplasticizer on cement is 5.33 mg/g with Langmuir adsorption isotherm mode.更多还原