聚羧酸减水剂分子质量及其分布对分散性的影响

摘要

以丙烯酸和501醚类单体为主要原料,改变偶氮二异丁腈(AIBN)、巯基丙酸的用量以及酸醚比,合成了一系列具有不同重均分子质量及其分布的聚羧酸减水剂,对产物进行了红外光谱和凝胶渗透色谱分析,研究了聚羧酸减水剂重均分子质量、分子质量分布对其分散性能的影响及其原因.结果表明,聚羧酸减水剂的重均分子质量对分散性能的影响显著,只有当聚羧酸减水剂具有适宜的重均分子质量及其分子质量分布时,才能具有优良的分散性.%With acrylic acid and 501 ether macromonomer as main raw materials,a series of polycarboxylate superplasticizers which possessed different weight average molecular weight and molecular weight distribution were prepared by changing the dosage of the azodiisobutyronitrile(AIBN),mercapto propionic acid and molar ratio of acid and ether. The products were characterized using Fourier transform infrared spectromet analysis and gel permeation chromatography analysis,the influence of weight average molecular weight and molecular weight distribution of the polycarboxylate superplasticizer on its dispersion property and its canse were also investigated. The results demonstrated that the average molecular weight of the products had the most significant influence on the dispersion property. The polycarboxylate superplasticizer showed excellent dispersion performance only when the product has appropriate average molecular weight and molecular weight distribution.