journal article·2026-06Open access

Structure–property relationships in multifunctional starch/agar biocomposite films reinforced with alkaline–peroxide treated hemp fibers for sustainable applications

Kemal Çağatay Selvi, Ehsan Fartash Naeimi, İbrahim İnanç, Nicoleta Ungureanu

Abstract

ABSTRACT As plastic pollution worsens globally, developing biocomposite films has become essential for a cleaner and more sustainable future. In this study, nine biocomposite films were prepared by solution casting using a fixed starch amount (3 g) with varied agar proportions (0%, 50%, and 75% of starch weight) and alkaline hydrogen peroxide-treated hemp fibers (0%, 15%, and 30% of the total starch–agar mass). Films were evaluated for color parameters (total color difference, yellowness index, and whiteness index), moisture content, water absorption, water solubility, and biodegradability (over three months), and analyzed by differential scanning calorimetry, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Results showed increasing hemp fiber content increased total color difference and yellowness index, while agar improved surface uniformity and whiteness. Adding agar significantly (p < 0.05) reduced moisture content, while water absorption increased with higher fiber loading. Water solubility was greatest in films containing starch, 50% agar and hemp. After three months in soil, starch-based and starch/hemp fiber films completely decomposed, whereas starch/agar and starch/agar/hemp fiber films degraded partially (about 52–75%), indicating that agar’s higher density limited microbial activity. The analysis confirmed strong hydrogen bonding between polysaccharides and hemp fibers, reducing crystallinity and affecting thermal stability. Scanning electron microscopy images showed good interfacial adhesion at 15% hemp loading but some agglomeration at 30%. Overall, films composed of starch with 50% agar and hemp fibers provided the most balanced overall performance among the tested formulations in terms of structural integrity, moisture resistance, and biodegradability, making them promising candidates for sustainable applications.
Source: openalex_inverted_index · Quality: baseline

Research context

OpenAlex topics: Natural Fiber Reinforced Composites · Nanocomposite Films for Food Packaging · Advanced Cellulose Research Studies

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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