磷酸改性氯氧镁水泥耐水机理的研究  

Research on the mechanism of water resistance of magnesium oxychloride cement with phosphoric acid

作　　者：陈雪霏[1] 王路明[1] 

机构地区：[1]盐城工学院材料工程学院,江苏盐城224051

出　　处：《混凝土》2018年第2期68-71,共4页Concrete

基　　金：国家自然基金资助项目(5167021646)

摘　　要：磷酸及可溶性磷酸盐是当前用于改善氯氧镁水泥耐水性最为有效的改性剂,但其耐水机理仍未确定。认为附着在水化产物晶相表面的不溶性磷酸盐膜层应当是阻止或抑制水化产物水解的主要因素,由于氯氧镁水泥的凝结硬化速度较快,[PO4]3-与Mg2+在水化产物晶相表面的迁移很困难,磷酸盐难形成晶相,应为无定形不规则分布。虽然通过XRD等分析手段未发现有磷酸盐晶相的形成,但通过表面研究的方法,不仅可提高氯氧镁水泥的耐水性,还检测出磷酸盐的存在。Phosphoric acid and soluble phosphate were the most effective modifiers for improving the water resistance of magnesium oxychloride cement （MOC） ,but the mechanism was still not deterrnined.It was considered that the insoluble phosphate covering the surface of the crystal product was the main factor of blocking or inhibiting the hydrolysis of hydration products.Because the coagulation hardening speed of MOC was very fast,the migration of [PO4]3- and Mg2. in the surface of the crystal product was very difficult.Phosphate was difficult to form crystalline phase, so their distribution were amorphous and irregular.The insoluble phosphate crystals were not found by XRD ,but in this test,they were detected.It was investigated by the method of surface research,and it could not only improve the water resistance of MOC, but also prove the existence of phosphate.

关 键 词：氯氧镁水泥 耐水性 磷酸盐 浸渍 

分 类 号：TU528.041[建筑科学—建筑技术科学]