保坍型聚羧酸系减水剂的合成及其分子质量测试研究

Study on the synthesis and molecular mass measurement of slump-preserving polycarboxylate water-reducing agent

采用TPEG聚醚合成保坍型聚羧酸系减水剂P-1,并对其结构、性能进行分析,研究了凝胶色谱法测试减水剂P-1分子质量的影响因素,并对减水剂P-1的储存稳定性进行考察。试验结果表明:减水剂P-1的分子结构符合预期,其净浆和混凝土性能均优于市售保坍型聚羧酸系减水剂P-2和P-3;采用凝胶色谱法测试减水剂P-1的分子质量时,适宜的流动相为含0.05%NaN_(3)的0.1 mol/L NaNO_(3)溶液、流速为(0.8~1.0)mL/min、检测器灵敏度为8~16、溶样时间为1 min;减水剂P-1于常温贮存6~12个月后其分子质量和混凝土应用性能无明显变化,稳定性良好。

TPEG polyether was used to synthesize the slump-preserving polycarboxylate water-reducing agent P-1,and its structure and performance were analyzed.The best parameters for testing the molecular mass of the slump retention type polycar-boxylate water reducing agent P-1 by gel chromatography were studied,and the storage stability of the slump-preserving polycarboxylate water-reducing agent P-1 was investigated.The results show that the structure of the slump retention type polycarboxylate water reducing agent P-1 is in line with expectations,and its properties of cement paste and concrete are better than those of the commercially available slump retention type polycarboxylate water reducing agents P-2 and P-3.When using gel chromatography to test the molecular mass of the slump retention type polycarboxylate water reducing agent P-1,select a 0.1 mol/L sodium nitrate solution containing 0.05% sodium azide for flow,and the flow rate should be(0.8~1.0)mL/min.The sensitivity of the detector should be 8~16.It is recommended that the sample dissolving time is 1 min.The slump-preserving polycarboxylate water-reducing agent P-1 has good stability in molecular mass and concrete performance after being placed at room temperature for 6~12 months.