聚羧酸系减水剂对铝酸盐水泥性能的影响

Influence of polycarboxylate based plasticizer on the properties of the alumina cement

测定了自制聚羧酸高效减水剂不同掺量对铝酸盐水泥净浆扩展度、凝结时间及胶砂强度的影响,通过扫描电镜测试了水化产物的形貌,对聚羧酸高效减水剂对铝酸盐水泥早期结构的作用机理进行了分析。结果表明:使用自制聚羧酸高效减水剂在适宜掺量时能显著提高铝酸盐水泥的净浆扩展度,并且具有良好的扩展度保持性能;标准稠度时,聚羧酸高效减水剂的掺入使铝酸盐水泥净浆的初凝时间略有延长,随掺量的增大会显著延长终凝时间;相同水灰比时,较低掺量聚羧酸高效减水剂对铝酸盐水泥的1d抗折强度和抗压强度影响不大,掺量大于0.6%时,会显著降低铝酸盐水泥的1d抗折强度和抗压强度,但聚羧酸高效减水剂掺量不同,对铝酸盐水泥胶砂3d抗折强度和抗压强度影响不大。

The influences of self made polycarboxylate based plasticizer on the fluidity of paste,initial and final setting time of paste and mechanical properties of mortar of alumina cement was investigated.The morphology of the hydration products was observed by scanning electron microscope（SEM）.Mechanism of the superplasticizer on the early structure of alumina cement was represented.The results showed that the self made polycarboxylate based plasticizer at appropriate dosage can raise the fluidity of paste,improved losses of fluidity,postpone the initial and final setting time of paste of alumina cement.The self made polycarboxylate based plasticizer at excessive dosage can reduced the compressive and flexural strength at 1 days.However,self made polycarboxylate based plasticizer slightly affect the compressive and flexural strength at 3 days.