Effects of Areca Husk Fiber Loading and Alkaline Treatment on Properties of Natural Rubber Latex Foam

The impact of integrating areca husk fiber (AHF) and employing alkaline treatment on the mechanical, thermal, and morphological characteristics of natural rubber latex foam (NRLF) is examined in this research. Areca husk fibers, derived from agro-industrial waste, were included in the NRLF matrix at different loadings (0, 5, 10, 15, 20, and 25 pphr). The fibers were chemically treated with sodium hydroxide (NaOH) to enhance surface roughness and augment interfacial interaction with the NRLF. Tensile tests indicated enhanced tensile strength at the appropriate filler load of 15 pphr for untreated AHF and 10 pphr for treated AHF. The elongation at break was decreased as fiber loadings increased, with greater elongation exhibited by treated AHF-filled NRLF compared to untreated AHF-filled NRLF. The foam’s density and compression set increased with elevated fiber loadings; however, treated AHF-filled NRLF demonstrated improved elasticity and thermal stability compared to untreated samples. Filler-matrix interactions were validated through scanning electron microscopy (SEM), which showed reduced cell sizes and more homogeneous foam formations in the treated AHF samples. The results indicate that the efficacy of NRLF is enhanced by the alkaline treatment of AHF, rendering it an appropriate material for sustainable composite applications. HIGHLIGHTS Integration of sustainable materials: Areca husk fiber (AHF), an agro-industrial byproduct, was utilized as a filler in natural rubber latex foam (NRLF), fostering environmentally friendly composite materials. Enhancement of alkaline treatment: Alkaline-treated AHF markedly improved mechanical properties, including tensile strength, elongation, and foam density, in comparison to untreated fibers. The maximum tensile strength was attained at 15 pphr for untreated AHF and 10 pphr for treated AHF. Thermal stability: Treated AHF-filled NRLF demonstrated better thermal stability and resistance to degradation compared to untreated counterparts. Improved foam morphology: Alkaline treatment resulted in smaller, more uniform foam cells, enhancing the foam structure and overall mechanical performance. GRAPHICAL ABSTRACT