Fabrication and Characterization of <i>Grewia mollis</i> Fiber/Polyester Nano Composite for Potential Automotive Applications

The growing demand for sustainable and lightweight materials in the automotive industry has led to the investigation of natural fiber-reinforced polymer composites as alternatives to conventional synthetic materials. This study investigated the formation of a nano composite using Grewia mollis fiber and nano-cellulose derived from Dialium guineense (Velvet Tamarind) wood pulp for potential automotive interior applications. Grewia mollis fibers were subjected to alkaline treatment using sodium hydroxide (NaOH) at concentrations of 0%, 5%, 10%, 15%, 20%, and 25%. The treated fibers were characterized to determine their moisture, water absorption, and density. Results showed that NaOH treatment significantly improved the physical properties of the fibers, with the 10%–20% treatment range yielding ideal moisture resistance and structural compactness. Simultaneously, nano-cellulose was extracted from Dialium guineense wood pulp using a combination of acid hydrolysis and mechanical refining. The nano-cellulose was characterized using Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM), which confirmed the successful removal of lignin and hemicellulose and the presence of nanoscale fibrillar structures. The treated fibers and nano-cellulose were then incorporated into a polyethylene matrix to form composite panels through hand lay-up casting in an aluminum mold. The resulting nanocomposites exhibited improved physical properties, indicating their potential use in automotive applications where lightweight, moisture-resistant, and biodegradable materials are desirable. By introducing Grewia mollis as a feasible reinforcement material and showcasing the efficient use of nano-cellulose derived from agro-waste as a performance-enhancing filler, this study adds to the body of knowledge on natural fiber-reinforced composites.