Exploring superplasticizers impact on MgO-based binder

The production of conventional Portland cement significantly contributes to global carbon dioxide (CO2) emissions and energy consumption. Driven by the imperative of sustainable practices, exemplified by the adoption of magnesium oxide (MgO) for its energy efficiency and carbon-mineralization potential, alongside advancements in civil engineering is a pressing need to comprehensively investigate both the rheological and mechanical properties of this eco-friendly material. Superplasticizers are crucial in this regard, as they can alter particle interactions and potentially delay cement hydration. This study examines the significant impact of superplasticizers on both the fresh and hardened characteristics of MgO-based binders. Through a systematic investigation, we analyze the influence of seven distinct superplasticizers on the rheological and mechanical properties of MgO-based binders across two phases. In the initial phase, an extensive screening process is conducted to identify the most effective superplasticizers and determine their optimal dosage based-on workability and mechanical properties. Subsequently, three well-performing superplasticizers are selected for further analysis of their effect on MgO hydration. In the second phase, we conduct a detailed study of the selected superplasticizers’ impact on phase assemblage, microstructure, hardening characteristics, and rheology. This endeavor aims to provide profound insights into the optimization and fundamental properties of MgO-based binders enhanced with superplasticizers, thereby advancing our understanding of their practical applicability in construction scenarios.