Author(s)

Hao Wang, ChuanWei Zhang^*

Affiliation(s)

College of Mechanical and Electrical Engineering, Qingdao University, Qingdao 266071, Shandong, China.

Corresponding Author

ChuanWei Zhang

ABSTRACT

Unlike traditional petroleum-based thermoplastic films, starch-based films rely on solvent systems and cannot be processed thermally, resulting in low production efficiency and hindering large-scale industrial applications. This study developed a dual-modification method combining enzymatic hydrolysis, dual cross-linking, and plasticizers to prepare enzyme-crosslinked thermoplastic starch (ECSS). High-toughness and transparent films were fabricated via hot-pressing technology. Enzymatic hydrolysis reduced starch crystallinity and molecular chain entanglement, facilitating subsequent cross-linking reactions. Citric acid (CA) and sodium trimetaphosphate (STMP) synergistically constructed a dense molecular cross-linked network through esterification and phosphorylation, respectively. With the assistance of plasticizers, the tensile strength of the film increased by 62.3%, and the elongation at break reached 348.7%. Thermogravimetric analysis (TGA) confirmed that dual cross-linking significantly enhanced thermal stability. Differential scanning calorimetry (DSC) revealed a reduced glass transition temperature (Tg), indicating improved thermoplasticity. X-ray diffraction (XRD) demonstrated that cross-linking effectively disrupted the crystalline structure of starch, forming a stable amorphous network.

KEYWORDS

Thermoplastic starch; Enzymatic hydrolysis; Cross-linking; High-toughness film

CITE THIS PAPER

Hao Wang, ChuanWei Zhang. Preparation of high-toughness thermoplastic starch films via enzymatic hydrolysis and cross-linking modification. Frontiers in Environmental Research. 2025, 3(1): 56-68. DOI: https://doi.org/10.61784/fer3020.

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