聚羧酸减水剂的合成与分散吸附性能研究

Study on synthesis and dispersive adsorption properties of polycarboxylate water-reducing agent

通过酸醚比及氧化剂、还原剂、链转移剂用量等合成因素调控聚羧酸减水剂(PCE)的分子结构,采用水泥吸附量测试、流动度测试,考察分析了不同合成因素对PCE分散、吸附性能的影响。结果表明:随着酸醚比的增大,PCE的分散性随之提高,吸附能力先增大后减小,当酸醚比为3.72时,PCE的吸附性能最好;当n(过硫酸铵)∶n(TPEG)=0.07时,PCE的分散性最好;n(过硫酸铵)∶n(TPEG)=0.06时,PCE的吸附性能最好;当n(次磷酸钠)∶n(TPEG)=0.17时,PCE的分散性和吸附性能最好;当n(巯基乙酸)∶n(TPEG)=0.07时,PCE的分散性最好;随减水剂掺量增加,水泥净浆流动度和吸附量均增大。

The molecular structure of polycarboxylate water-reducing agent(PCE)is adjusted by synthetic factors such as acid-to-ether ratio,oxidant dosage,reducing agent dosage,chain transfer agent dosage,etc.Adopt cement adsorption capacity test and fluidity test analysis method to investigate the influence of different synthesis factors on PCE dispersion and adsorption performance.The study found that as the acid-to-ether ratio increases,the dispersing performance of PCE also increases,and the adsorption capacity first increases and then decreases.When the acid-to-ether ratio reaches 3.72,the adsorption effect of PCE is the best;When the molar ratio of the ammonium persulphate to TPEG is 0.07,the dispersion performance of PCE is the best.When the molar ratio of ammonium persulphate to TPEG is 0.06,the adsorption effect of PCE is the best.When the molar ratio of sodium hypophosphite to TPEG is 0.17,the dispersion and adsorption effect of PCEG is the best.When the molar ratio of thioglycolic acid to TPEG is 0.07,the dispersibility and adsorption effect of PCE is the best,as the amount of water reducing agent increases,the dispersibility and adsorption performance of PCE also become better.