Abstract:
Via radical polymerization, three polyurethane-modified polycarboxylate molecules of various comb topologies were synthesized. This study investigated the effects of varying types and concentrations of supplementary cementitious materials (SCMs) on the surface tension, flowability, and zeta potential of cement. An elevation in the molar ratio between isoamyl alcohol polyoxyethylene (TPEG) and acrylic acid (AA) from 1:1 to 5:1 reduced the surface tension of the polycarboxylate molecule from 47.70 mN/m to 35.53 mN/m and increased flowability from 280 mm to 310 mm, as the results indicated. An increase in the SCM and polycarboxylate dosage proportionally decreased liquid-phase surface tension and increased flowability. A decrease in the water-to-cement (w/c) ratio from 0.5 to 0.3 corresponded to an observed increase in the zeta potential of cement pastes. However, a rise in the quantity of polycarboxylate and SCMs corresponded to a decrease in the zeta potential at a w/c ratio of 0.3.
摘要:
通过自由基聚合,合成了三种不同梳形拓扑结构的聚氨酯改性聚羧酸酯分子。这项研究调查了不同类型和浓度的补充胶凝材料(SCMs)对表面张力的影响,流动性,和水泥的zeta电位。异戊醇聚氧乙烯(TPEG)和丙烯酸(AA)之间的摩尔比从1:1提高到5:1,聚羧酸酯分子的表面张力从47.70mN/m降低到35.53mN/m,流动性从280毫米增加到310毫米,正如结果表明的那样。SCM和聚羧酸盐用量的增加成比例地降低了液相表面张力并增加了流动性。水与水泥(w/c)比从0.5降低到0.3对应于观察到的水泥浆zeta电位的增加。然而,在w/c比为0.3时,聚羧酸盐和SCM的量的增加对应于ζ电位的降低。