METHOD AND COMPOSITIONS FOR IMPROVING PERFORMANCE PROPERTIES OF MAGNESIUM OXYCHLORIDE CEMENTS.

摘要

Despite the excellent properties associated with Magnesium OxyChloride (Sorel) based cements and Magnesium OxySulfate based cements, water and corrosion resistance has been limiting factors for achieving greater commercial applications. Such issues can be addressed by incorporating various alkali metal phosphates, such as Magnesium mono- or dihydrogen phosphate (MgHPO4 or MgH2PO4) with alkali metal fatty acids; such as Magnesium Stearate; and metal or alkali metal sulfates such as Aluminum Sulfate or Magnesium Sulfate. Water resistance is further enhanced by either pre-carbonating the mix water or the liquid magnesium chloride phase of the cements, or by adding a carbonate into the powder phase. Accelerated cure of this system has also been obtained by using various inorganic metal oxides. Additionally, improved corrosion resistance is achieved through the use of certain phosphates, zeolites, nitrites and other novel additives.