Formulation and characterization of a sustainable biopolymer derived from sugarcane bagasse: A comparative study of mechanical, thermal and functional properties

The global surge in plastic pollution and the environmental persistence of non-biodegradable polymers have intensified the search for sustainable alternatives derived from biomass. This study explores the valorization of sugarcane bagasse, an abundant agricultural residue to develop a bio-based polymer capable of serving as a functional alternative to petroleum-derived plastics. The biopolymer was synthesized through the extraction of lignocellulosic fractions and subsequently characterized against a commercial petroleum-based plastic (LDPE) control. Structural and morphological analyses were performed using Fourier Transform Infrared (FTIR) spectroscopy, Scanning Electron Microscopy (SEM), and Energy-Dispersive X-ray Spectroscopy (EDS). Results indicate that the biopolymer possesses a distinct fibrous microstructure and a lignocellulosic backbone, as evidenced by characteristic 𝑂−𝐻 stretching at 3341 cm−and C=O peaks related to hemicellulose. Thermal analysis revealed a significant performance advantage, with the biopolymer exhibiting a thermal stability of 284.20∘C substantially exceeding that of the commercial standard (174.10∘C). While mechanical testing showed a lower tensile strength (6.2 MPa) compared to the control (30.8 MPa), the biopolymer offered a reduced density (0.933 g/ml), suggesting suitability for lightweight, low-load packaging applications. Functional characterization demonstrated a Water Absorption Capacity (WAC) of 49.70% and an Oil Absorption Capacity (OAC) of 36.48%, alongside a swelling power of 15.65%. These findings suggest that sugarcane bagasse-derived bio plastics are viable, thermally superior suitable for the circular economy, particularly in applications requiring grease resistance and high-temperature processing.