Enhancing the Mechanical and Moisture Resistance Properties of Plaster of Paris Using Nano-Silica, Glass Fibres, and Polyvinyl Alcohol

Plaster of Paris (POP) is widely utilised in construction and artistic applications, yet its limited mechanical strength and sensitivity to moisture remain significant technical challenges. This study investigates the effects of incorporating nanosilica, glass fibres, and polyvinyl alcohol (PVA) on the performance of POP-based composites. Various formulations were evaluated for compressive, flexural, and hardness strengths, as well as water absorption. The experimental protocol distinguished between two immersion conditions: a 2 h immersion period was employed specifically for water absorption testing, while mechanical properties (compressive, flexural, and hardness) were evaluated under wet conditions following a 6 h immersion period. Results demonstrate that integrating nano-silica, glass fibres, and PVA increases mechanical resistance and reduces water uptake. Microscopic analysis indicates that nano-silica particles densify the POP matrix through a microfiller effect. These findings suggest that the modified POP composites exhibit improved performance for short-term moisture exposure, although further research is required to assess long-term durability in aqueous environments.