Preparation of drying powder inorganic polymer cement based on alkali-activated slag technology

Abstract

In the alkali activated inorganic polymer preparation process, liquid water glass is used as an alkali-activator to dissolve the solid aluminosilicate precursor and form the cement material. However, liquid water glass is not convenient for storage or transportation. Developing an inorganic polymer-based powder cement (IPBPC) as a one-part mixture (“just add water”), similar to Portland cement, increases its commercial viability. Through compressive strength and heat flow analysis, this paper presents research on the mechanical properties and reaction process of slag with solid or liquid water glass; in contrast, solid water glass has better mechanical performance. The L9(34) orthogonal experiment method is used to optimize the experimental formula. According to the range analysis and SEM, this result indicates that the level of significance of factors are as follows: m(SL)/m(WG)>fly ash>water>retarder; m(SL)/m(WG) has the most significant impact on the 7-day compressive strength of the IPBPC sample. The 29Si solid-state NMR patterns demonstrate that in the IPBPC sample with m(SL)/m(WG)=5:1, primarily Q2 and Q2(1Al), the Al can incorporate into the gel. The optimum formula is as follows: m(SL)/m(WG)=5:1, retarder 7%, fly ash 10%, and water 28%. The 7-day compressive strength of the optimum composition is 67.38MPa, the initial setting time is 150min, and the final setting time is 230min and meets the construction conditions.