Thermoplastic bio-composites from natural Samanea Saman fillers loaded HDPE: Mechanical, thermal, and structural analysis
C. Balaji Ayyanar, K. Marimuthu, S. K. Pradeep Mohan, B. Gayathri, C. Bharathiraj, Resego Phiri, Femiana Gapsari, Putu Hadi Setyarini, Sanjay Mavinkere Rangappa, Suchart Siengchin
Abstract
This study explores the potential of biodegradable Samanea saman (SS) flower fillers as reinforcements in high-density polyethylene (HDPE) composites, fabricated using injection molding techniques at various filler concentrations. Surface morphology and elemental composition were analyzed using Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDX), revealing a composition predominantly of Carbon (88.04 %), along with Oxygen, Silicon, Chlorine, Potassium, Calcium, Sodium, and Bromine. The crystal structure of the fillers was identified as orthorhombic via X-ray diffraction (XRD), and the crystallite size was measured at 62.78 nm. Thermal stability assessments conducted through Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) indicated stability up to 210 °C before degradation occurred. Mechanical properties were optimized at a filler content of 40 wt% for Shore D hardness (63.5 ± 0.5 SHN) and compressive strength (25.5 ± 0.5 MPa), and at 30 wt% for tensile (23.5 ± 0.5 MPa) and flexural strength (19.5 ± 0.5 MPa). These results suggest that SS-HDPE composites offer a viable, environmentally friendly alternative for non-load-bearing applications, potentially reducing HDPE usage by up to one-third. • The method used injection molding to create composites with biodegradable Samanea saman flower fillers. • Applied EDX and FESEM characterized the composite surfaces and elemental composition. • The results showed that elements such as carbon and oxygen were predominant, with composites stable up to 210 °C. • The highest mechanical strengths were observed at higher filler concentrations. • The study demonstrates potential for reducing plastic use and enhancing environmental sustainability.