阳离子单体对聚羧酸减水剂早强性能的影响

Effect of Cationic Monomer on Early Strength Performance of Polycarboxylate Superplasticizer

合成了阳离子单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)引入量不同的聚羧酸减水剂,采用傅里叶红外光谱进行了结构确证。通过水泥净浆流动度、凝结时间、净浆和胶砂抗压强度测试,研究了阳离子单体不同引入量对聚羧酸减水剂分散性、凝结时间和早强性能的影响。通过XRD、TG对作用机理进行了分析。结果表明:DMC引入量占大单体4%时,净浆流动度达到最大值;引入DMC后,净浆凝结时间缩短,净浆和胶砂试件早期抗压期强度明显提高;当引入量占大单体12%时早强性能最好。由XRD和TG分析可知,引入DMC促进了C3S的早期水化,生成较多的水化硅酸钙和氢氧化钙。

Polycarboxylate superplasticizers with different dose of cationic monomer methacrylatoethyl trimethyl ammonium chloride（ DMC） were synthesized. The structure were determined by FTIR. The effect of different dose of cationic monomer on dispersion,setting time and early compressive strength of polycarboxylate superplasticizer were studied through the fluidity of cement paste,the setting time of cement paste and the compressive strength of cement paste and mortar. The reaction mechanism was discussed with XRD and TG. The results show that the maximum fluidity was achieved under the dose of4% of macromonomer,the setting time of cement paste is shorted,and the early compressive strength of cement paste and mortar has an obvious improvement. The value of early strength is highest when DMC was the 12% dose of macromonomer. It indicated that DMC promoted the early hydration of C3 S and generated more calcium-silicate hydrate and calcium hydroxide by XRD and TG methods.