聚合物乳液对水泥砂浆流变性能的影响

摘要

采用流变学测试方法,研究了聚合物乳液对水泥砂浆屈服应力、蠕变恢复、动力黏度及触变性的影响.结果表明;水泥砂浆屈服应力随着聚合物乳液掺量的增加而急剧增大,最大增至普通水泥砂浆的9.62倍;水泥砂浆蠕变在外力作用下逐渐增大,撤销外力后出现瞬时恢复,之后保持恒定,蠕变恢复能力随着聚合物乳液掺量的增加而增大,最大增幅在100倍左右;水泥砂浆动力黏度随剪切时间的增加而不断减小,聚合物乳液掺量的增大加剧了动力黏度减小的趋势;在触变性试验中随着聚合物乳液掺量的增加,水泥砂浆结构破坏后的恢复能力不断增强,最大增幅为72.57％.%The yield stress,creep and recovery,dynamic viscosity and thixotropic properties of cement mortar by adding polymer latex were investigated by using rheological test method.The yield stress of cement mortar increases sharply with the increasing polymer latex content,the maximum growth is 9.62 times that of ordinary cement mortar.Creep variables increases gradually under the action of external force.After instantaneous recovery the creep variables kept constant,the recovery ability increases with the increase of polymer latex,to about 100 times.The dynamic viscosity decreases with the increase of shear time.The increase of polymer latex content exacerbates the trend of dynamic viscosity reduction.With the increase of polymer latex content,the recovery ability of the structure increases in thixotropy test,up to maximum increase of 72.57％.