Characterization and Performance Enhancement of Bio-Based Polyurethane-Modified Cement Mortar Utilizing Polyglycerol Polyester Polyol

The increasing focus on sustainable construction is driving the industry toward materials that combine functionality with environmental benefits. A viable approach to address this demand is the use of bio-based additives to improve traditional cementitious composites. This study introduces a novel approach to developing a polymer-modified construction material by incorporating varied amounts (0, 1, 2, 3, and 6%) of bio-based polyurethane (PU), derived from polyglycerol polyester polyol, into cementitious mortar. The resulting PU-modified cementitious mortar (PUMC) was evaluated for its mechanical, physicochemical, and microstructural properties. Results show that the incorporation of 2% PU by cement weight significantly enhanced compressive strength by 58.2%, flexural strength by 37.0%, and initial flow performance by 20.0% after 28 days, while a 6% PU incorporation provided the best abrasion resistance. These improvements were attributed to a uniform particle and pore size distribution and the formation of a uniform interpenetrating polymer network (IPN), as confirmed by BET-BJH and SEM-EDX analyses. Additionally, FTIR and TGA analyses revealed that the metal-ligand coordination between Ca²⁺ ions in the cement mortar and PU ligand groups strengthened the interfacial connectivity through noncovalent bonding, further enhancing the material properties. This research highlights the potential of bio-based PU as an eco-friendly additive that significantly improves the performance of cementitious mortars, making it a promising option for industrial flooring applications.