亚硫酸氢钠复合引发体系在聚羧酸减水剂中的应用

The application of complex initiation system of sodium hydrogen sulfite in polycarboxylate superplasticizer

以甲基烯丙基聚氧乙烯基醚(TPEG)聚醚大单体为原料,以亚硫酸氢钠/过硫酸铵为复合引发体系,通过水溶液聚合制备高性能聚羧酸减水剂。实验结果表明,亚硫酸氢钠/过硫酸铵复合引发体系制备聚羧酸减水剂的最佳工艺为:反应温度60℃,n(亚硫酸氢钠)∶n(过硫酸铵)=1∶5,过硫酸铵用量为大单体质量的2.0%,丙烯酸用量为大单体质量的10%。该工艺制备的减水剂具备较高的分散性及分散保持性。

High performance polycarboxylic acid water-reducing agent was prepared via aqueous solution polymerization. TPEG polyether was used as monomer and sodium hydrogen sulfite/ammonium persulfate was used as complex initiation system. The optimum preparation procedure of water-reducing agent through ammonium persulfate/sodium hydrogen sulfite complex initiation system was demonstrated as follows：the dosage of ammonium persulfate is 2% of the macromolecular monomer,the ratio of sodium hydrogen sulfite to ammonium persulfate is 1/5,the dosage of acrylic acid is 10% of the macromolecular monomer and the reaction temperature is 60 ℃. The polycarboxylic acid water-reducing agent prepared via this process was demonstrated to have high waterreducing rate and superior dispersion stability.