Development and characterization of sisal fiber-reinforced wood dust/polystyrene for sustainable ceramic application

The emphasis of sustainable materials in ceramic and construction materials has renewed interest in natural fiber reinforced with polymer composites. In this study, four formulations (sisal: 80–55 wt%; polystyrene: 15–40 wt% and wood dust constant (5 wt%) were characterized for density, flexural and tensile strength, hardness, water absorption and moisture content. The density decreased slightly with reduced the fiber content (302–281 ± 2.5 kg.m −3 ). The mechanical performance also improved with increasing matrix fraction: the highest flexural strength (24.1 ± 1.18 MPa), tensile strength (29.5 ± 1.14 MPa) and hardness (76 ± 3.18 HRB) were obtained at 55 wt% sisal, 5 wt% wood dust and 40 wt% of polystyrene. Conversely The water absorption and moisture content of the fabricated composite exhibited the highest value (8.94 ± 0.4% and 7.04 ± 0.35%) with higher sisal fiber content 80 wt% (15 wt% polystyrene); the recommended 55/5/40 composition exhibited substantially lower water absorption (1.5 ± 0.09%) and moisture content (2.21 ± 0.11%). The SEM and XRD analyses indicating improved fiber wetting and reduced porosity in matrix rich specimens, while the higher fiber fractions show greater crystallinity but poor impregnation and higher hygroscopicity. From the result identifies the 55/5/40 (sisal/wood dust/polystyrene) composition as the best compromise between the mechanical performance and moisture resistance. The obtained result of the composite offers promising potential as sustainable, lightweight materials for interior, dry-to-semi-humid ceramic backing layers, insulation components, and other non-load-bearing applications. High-fiber-content formulations (>70 wt% sisal) are not recommended for continuously wetted environments without additional surface sealing treatment.