聚丙二醇掺量对碱矿渣水泥砂浆性能和水化过程的影响

Effect of Polypropylene Glycol Content on Performance and Hydration Process of Alkali Activated Slag Cement Mortar

研究了不同掺量聚丙二醇对碱激发矿渣(AAS)水泥砂浆流动度、力学性能和干缩的影响,并通过电化学交流阻抗法(EIS)探讨了其对砂浆水化过程的影响。结果表明,聚丙二醇的掺入能够显著提高AAS水泥砂浆的流动性,且掺量越大,流动性提高越明显,但砂浆密度有轻微降低。聚丙二醇的掺入降低了AAS水泥砂浆的抗折、抗压强度,但是随着龄期的增长,抗折、抗压强度均有所提高。掺入聚丙二醇能有效降低AAS砂浆的干缩。当聚丙二醇掺量为1%~3%时,各龄期的孔溶液电阻值(R1)较基准组有所减小,聚丙二醇抑制了AAS砂浆的水化反应。当掺量为5%~9%时,各龄期的R1大于基准组,AAS砂浆水化反应加快,且R1随着聚丙二醇掺量的增加而增大。

The effect of different content of polypropylene glycol on the fluidity,mechanical properties and shrinkage of alkali-activated slag(AAS)cement mortar was studied,and its influence on hydration process of AAS mortar was discussed by electrochemical impedance spectroscopy(EIS).The results show that the polypropylene glycol can improve the fluidity of AAS cement mortar,and the greater the content of polypropylene glycol,the more obvious the fluidity increase,but the density of the mortar slightly decreases.The flexural and compressive strength of AAS cement mortar decrease with the addition of polypropylene glycol,but with the increase of age,the flexural and compressive strength increase.Polypropylene glycol can effectively reduce the shrinkage of AAS mortar.The pore solution resistance(R1)of AAS mortar is lower than that of the control group when the polypropylene glycol content is 1%~3%,polypropylene glycol inhibits the hydration reaction.When the content is 5%~9%,R1 is greater than that of the control group,the hydration reaction of AAS mortar is accelerated,and R1 increases with the increase of the polypropylene glycol content.