Open Access

ARTICLE

Enhancing Corn Starch-Poly(Vinyl Alcohol) and Glycerol Composite Films with Citric Acid Cross-Linking Mechanism: A Green Approach to High-Performance Packaging Materials

Herlina Marta¹, Novita Indrianti^2,*, Allifiyah Josi Nur Aziza³, Enny Sholichah⁴, Titik Budiati³, Achmat Sarifudin⁵, Yana Cahyana¹, Nandi Sukri¹, Aldila Din Pangawikan¹

1 Department of Food Technology, Faculty of Agro-Industrial Technology, Universitas Padjadjaran, Sumedang, 45363, Indonesia
2 Research Center for Process Technology, National Research and Innovation Agency, South Tangerang, 15314, Indonesia
3 Food Engineering, Agricultural Technology Department, Politeknik Negeri Jember, Mastrip, P.O. Box 164, Jember, 68121, Indonesia
4 Research Center for Molecular Chemistry, National Research and Innovation Agency, South Tangerang, 15314, Indonesia
5 Research Center for Food Technology and Processing, National Research and Innovation Agency, Cibinong, 16911, Indonesia

* Corresponding Author: Novita Indrianti. Email:

Journal of Renewable Materials 2026, 14(1), 8 https://doi.org/10.32604/jrm.2025.02025-0145

Received 22 July 2025; Accepted 20 October 2025; Issue published 23 January 2026

Abstract

Corn starch (CS) is a renewable, biodegradable polysaccharide valued for its film-forming ability, yet native CS films exhibit low mechanical strength, high water sensitivity, and limited thermal stability. This study improves CS-based films by blending with poly(vinyl alcohol) (PVA) or glycerol (GLY) and using citric acid (CA) as a green, non-toxic cross-linker. Composite films were prepared by casting CS–PVA or CS–GLY with CA at 0%–0.20% (w/w of starch). The influence of CA on physicochemical, mechanical, optical, thermal, and water barrier properties was evaluated. CA crosslinking markedly enhanced the tensile strength, water resistance, and thermal stability of CS–PVA films while increasing transparency in CS–GLY films. At 0.20% CA, the composite achieved 34.99 MPa tensile strength, reduced water vapor permeability, and minimized water uptake. FTIR confirmed ester bond formation between CA and hydroxyl groups of CS, PVA, and GLY, whereas thermal analysis showed higher decomposition temperatures and lower weight loss in crosslinked films. Increasing CA levels also decreased opacity and improved light transmittance, indicating greater homogeneity and reduced crystallinity. This dual-polymer matrix combined with a natural crosslinking strategy provides a sustainable route to high-performance, biodegradable CS-based packaging materials.

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Supplementary Material

Supplementary Material File

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