支化型聚羧酸减水剂的合成及其性能研究

Synthesis and performance study of branched polycarboxylate superplasticizer

使用环氧丙醇作为支化单体,制备了一系列支化度不同的支化型聚羧酸减水剂,通过凝胶渗透色谱表征和溶液黏度分析证实了合成聚羧酸分子的支化结构。通过净浆流动度、净浆流速、砂浆流动度、砂浆V漏斗流出时间、砂浆黏度和混凝土试验研究了支化型聚羧酸对水泥基材料性能的影响。结果表明,只要控制支化型聚羧酸的支化度在一定范围内,不仅不会降低聚羧酸的分散性,还能赋予它降低水泥基材料表观黏度的能力。

A series of branched type of polycarboxylate superplasticizers with different degrees of branching were synthesized employing glycidol as branched monomer.The branched architecture of the synthesized polycarboxylate was confirmed by gel permeation chromatography characterization and solution viscosity analysis.The effects of the branched type of polycarboxylate superplasticizers on properties of cement-based materials were investigated by fluidity of cement pastes,flow velocity of cement pastes,fluidity of mortar,V-funnel efflux time,viscosity of mortars and concrete experiments.It was found the water-reducing ability of polycarboxylate wouldn't be weakened when its degree of branching was limited within a certain range.Besides,the moderate branched structure would bring viscosity-reducing capacity on cement-based materials to polycarboxylate.