有机膦酸盐缓凝剂的合成及其对聚羧酸减水剂性能的影响

The synthesis of organic phosphonate retarders and its effect on the properties of polycarboxylate superplasticizers

采用有机胺单体通过曼尼希反应合成有机膦酸盐缓凝剂。通过与聚羧酸减水剂PCE复配后,考察了不同环境温度及含泥量(蒙脱土)下对PCE性能的影响。水泥净浆试验结果显示,合成的有机膦酸盐缓凝剂在低温下会降低PCE的初始分散性,在常温及高温条件下能提高PCE的初始分散和保坍性。吸附性能测试表明,有机膦酸盐缓凝剂能与PCE产生竞争吸附,在高温及含蒙脱土条件下,可以减少PCE的吸附,提高减水剂的分散、保坍性及抗黏土性能。有机膦酸盐缓凝剂的掺入延长了水泥的凝结时间。

In this paper,organic phosphonate retarders were synthesized by Mannich reaction with organic amine monomers.The effects of these retarders on the properties of polycarboxylate superplasticizer at different temperatures as well as anti-clay properties were investigated after they were mixed with polycarboxylate superplasticizers.The results of cement slurry experiments showed that the synthesized organic phosphonate retarders could reduce the initial dispersion of polycarboxylate superplasticizers at low temperatures,while they could improve the initial dispersion and slump retention performance of polycarboxylate superplasticizers at room temperatures and high temperatures.Adsorption isotherms measurement indicated that with the organic phosphonate retarders added,the competitive adsorption between retarders and PCEs was enhanced,the adsorption amounts of the PCEs could be reduced under the condition of high temperature and montmorillonite,so as to improve the dispersion and slump retention performance of the superplasticizers at high temperature as well as montmorillonite contains.The addition of organic phosphonate retarders can also effectively delay cement hydration and prolong the setting times of cement.