ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synergistic reinforcement of vinyl ester composites using silane-modified sesbania grandiflora stem fiber and palm oil fuel ash-derived Si₃N₄ particles

V. Shanmugam and Seeniappan Kaliappan

Department of Pharmaceutical Sciences, Mohan Babu University, Tirupati, India

E-mail: seeni_kali2927@outlook.com

Received: 5 May 2026  Accepted: 8 June 2026

Abstract:

Biocomposite materials have gained significant attention in recent decades due to their lightweight nature, low cost, environmental sustainability, and wide range of applications in automotive, aerospace, construction, and sports industries. In this study, a novel comparative investigation was conducted on silane-treated and untreated Sesbania grandiflora stem fiber and palm oil fuel ash-derived silicon nitride (Si₃N₄) particle reinforced vinyl ester composites. The composites were fabricated using the hand lay-up technique and evaluated according to relevant ASTM standards.The results revealed that silane treatment significantly enhanced the interfacial adhesion between the reinforcement and the vinyl ester matrix, leading to improved composite performance. Among the developed composites, TC2 containing 4 vol.% Si₃N₄ exhibited the highest mechanical properties, achieving a tensile strength of 114 MPa, flexural strength of 124 MPa, and impact strength of 5.0 J. These improvements were attributed to effective stress transfer, strong fiber–matrix bonding, and uniform filler dispersion.TC3 containing 6 vol.% Si₃N₄ demonstrated superior functional performance, exhibiting a hardness of 85 Shore-D, thermal conductivity of 0.42 W/mK, and the lowest water absorption of 0.49%, corresponding to a 42.35% reduction compared with the control composite. Furthermore, TC3 showed the greatest tribological improvement, with reductions of 26.92% in specific wear rate and 27.42% in coefficient of friction. The enhanced performance was primarily associated with the synergistic effect of silane treatment and the incorporation of palm oil fuel ash-derived Si₃N₄ particles.The findings confirm the effectiveness of silane surface modification in improving the overall performance of natural fiber-reinforced vinyl ester composites. While TC2 is most suitable for applications requiring high mechanical strength, TC3 is particularly advantageous for thermal management, wear-resistant, and moisture-resistant engineering applications.

Keywords: Polymer composite; Fiber; Silicon nitride particle; Silane treatment; SEM; Mechanical; Moisture absorption

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-05186-6

Chemical Papers 80 (11) 13373–13385 (2026)