Effect of natural cinnamon extract on the stabilizing properties of biodegradable packaging polymers
Anna Kosmalska-Olańska, Anna Masek
Vol. 20., No.1., Pages 52-71, 2026
DOI: 10.3144/expresspolymlett.2026.5
DOI: 10.3144/expresspolymlett.2026.5
GRAPHICAL ABSTRACT

ABSTRACT
The growing focus on sustainability, eco-friendly technologies, decarbonization, and reducing carbon footprints shapes current industry challenges. This article reviews the potential of cinnamon as a bio-additive for polymer stabilization in packaging. Samples were prepared from ethylene-norbornene copolymer (Topas), a cyclic olefin copolymer known for purity, transparency, and low gas permeability, and poly(lactic acid) (PLA), a bio-based alternative to petroleum plastics. Cinnamon powder was added in 0.5, 1.0, and 1.5 wt%. After solar and thermo-oxidative aging, hydrophobicity, chemical composition, mechanical, and color properties were analyzed. Results showed higher hydrophobicity and resistance to hydrolytic degradation due to reduced water penetration. PLA, normally brittle, became more flexible, with 0.5 wt% cinnamon showing optimal performance after 100 h of solar aging, similar to Topas composites. Overall, PLA and cyclic olefin copolymer (COC) films with cinnamon improved durability, extended food shelf life, and acted as natural color indicators of material aging.
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This is an editorial article. It has no abstract.
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