Cane grass-based: green boxes for packaging and thermal insulation

The use of sustainable materials plays a critical role in maintaining a clean environment and promoting public health in contemporary society. Polystyrene foam presents significant problems, both in packaging and thermal insulation for transporting medicines and meat. One promising alternative is cane parenchyma (CP)-based composite foam. CP was processed into chopped and crushed forms and combined with natural resins-starch and polyvinyl alcohol (PVA) to fabricate biodegradable foam. The foam was shaped into packaging boxes and evaluated for mechanical (compression: stacking and base strength) and thermal performance. Under compression testing, the chopped cane box achieved a stacking strength of 0.33 ± 0.04 MPa, compared with 0.27 ± 0.02 MPa for the crushed cane variant, both of which are substantially higher than the compressive strength of conventional polystyrene (0.17–0.2 MPa). The thermal conductivity of raw CP was measured at 0.05 ± 0.003 W/mK, while cane-resin composites ranged from 0.038 to 0.042 W/mK. Morphological analysis revealed interconnected air gaps within the foam matrix, quantified at 27 ± 8%, contributing to enhanced thermal insulation and energy absorption. These findings demonstrate the viability of cane parenchyma-based boxes as a mechanically superior, cost-effective (US$0.8–1 for cane boxes against US$1–2 for polystyrene), and sustainable alternative to expanded polystyrene for blister-style packaging applications.