Porous crosslinked CMC-PVA biopolymer films: Synthesis, standardization, and application in seed coating for improved germination

This study presents the development and characterization of crosslinked biopolymeric films composed of carboxymethyl cellulose (CMC) and poly(vinyl alcohol) (PVA) for seed coating applications. The films were synthesized using a solvent casting method integrated with physico-chemical crosslinking. Key formulation parameters—polymer concentration, crosslinker type, plasticizer, stirring speed, and temperature—were systematically optimized for improved film-forming ability and uniformity. The optimized films were evaluated for their impact on seed germination percentage, seed vigor index, and water permeability. Comprehensive characterization using SEM, TEM, XRD, FTIR, and TGA revealed a porous surface structure, effective crosslinking, and thermal stability. The films demonstrated high water absorption and low water vapor permeability (1.07 × 10⁻¹¹ g·m/Pa·s·m²), contributing to a significant enhancement in germination rates (up to 100 %). These results highlight the potential of CMC-PVA-based crosslinked films as environmentally friendly seed coatings, aligning with the goals of sustainable agriculture and the application focus of carbohydrate-based polymer technologies.