An exploratory study on cementitious matrices reinforced with microbial cellulose

This study evaluated the effect of microbial cellulose (MC) derived from Pythium aphanidermatum as a reinforcement in cement pastes, with and without steel fibers. A dosage of 1% MC was used, and the mechanical flexural behavior, along with physical properties, was evaluated after 28 days of curing. The analysis was complemented by epifluorescence microscopy, scanning electron microscopy (SEM), and thermogravimetric analysis (TG). The physical results demonstrated that the MC-modified matrix exhibited a lower water absorption percentage alongside higher apparent porosity and bulk density. Regarding flexural strength, the incorporation of MC (∼6 MPa) did not show statistically significant improvements. However, changes in the elastic modulus (∼1 GPa) suggest a modification in the stiffness of the matrix, indicating a more deformable mechanical response. SEM analysis revealed the agglomeration of MC within the cement matrix, while TG results indicated increased formation of hydration products, an effect associated with water retention and release within the MC structure. These findings suggest that MC can influence the microstructural and physical behavior of cementitious materials without significantly compromising mechanical performance. The study concludes that MC is a promising sustainable reinforcement for cement-based composites. However, further research is needed to improve dispersion methods, evaluate long-term effects, and explore different incorporation rates to optimize performance.