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This study investigates the structural and functional enhancement of corn zein–chitosan composites via mild alkaline treatment to develop biodegradable protein-polysaccharide materials for diverse applications. Films with varying zein-to-chitosan ratios were fabricated and characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Both untreated and sodium hydroxide (NaOH)-treated films were evaluated to assess changes in physicochemical properties. FTIR analysis revealed that NaOH treatment promoted deprotonation of chitosan’s amine groups, partial removal of ionic residues, and increased deacetylation, collectively enhancing hydrogen bonding and resulting in a denser molecular network. Simultaneously, partial unfolding of zein’s α-helical structures improved conformational flexibility and strengthened interactions with chitosan. These molecular-level changes led to improved thermal stability, reduced degradation, and the development of porous microstructures. Controlled NaOH treatment thus provides an effective strategy to tailor the physicochemical properties of zein–chitosan composite films, supporting their potential in sustainable food packaging, wound healing, and drug delivery applications.
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Development of A Biodegradable Tapioca Starch‐Based Polymeric Composite for Non‐Structural Applications
ABSTRACT This study presents a novel, bio‐based polymer composite derived from tapioca starch and reinforced with jute fibers, designed for non‐load bearing structural applications. The developed composite demonstrated significant thermal stability, with a single decomposition reaction observed above 300°C via TGA, surpassing many synthetic polymers. DSC analysis revealed a glass transition temperature (Tg) of 69.55°C and notable thermal energy storage capability. Mechanical characterization, including three‐point bending, tensile, and compressive tests, confirmed effective fiber wetting and a tensile strength of 9 MPa for the composite. Furthermore, the composite exhibited mild electrical conductivity of 3.62 × 10−7 S/m. Structural characterizations (SEM, XRD, FTIR) revealed the presence of an N‐H bond, a functional group common in conductive polymers, suggesting its potential as a mild conductor. Density functional theory simulations provided further insights into the biopolymer's molecular structure. This research highlights the promising potential of tapioca starch composites for various engineering applications, particularly as sustainable packaging materials.
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- Award ID(s):
- 2418415
- PAR ID:
- 10643825
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- SPE Polymers
- Volume:
- 6
- Issue:
- 4
- ISSN:
- 2690-3857
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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