A novel approach to the production of polymer products with enhanced antimicrobial effect and high UV aging resistance
Angelika Plota-Pietrzak, Anna Masek, Aleksandra Jastrzębska
Vol. 19., No.1., Pages 60-75, 2025
DOI: 10.3144/expresspolymlett.2025.5
DOI: 10.3144/expresspolymlett.2025.5
GRAPHICAL ABSTRACT

ABSTRACT
Herein, a novel approach was developed for the introduction of stabilizing compounds into polymers through a pre-impregnation process prior to processing, which is expected to improve their dispersion and, consequently, increase their efficacy. Ethylene-norbornene copolymer (EN) pellets were impregnated with quercetin or rutin in ethanol or a mixture of solvents (ethanol-dioxane (3:1)) for 24 h. Then, EN-based samples containing impregnated pellets were manufactured using a laboratory extruder. The research demonstrated that the materials containing impregnated pellets exhibited improved thermo-oxidation resistance, higher antibacterial effect (the number of dead cells increased from 8 to 59%), and satisfactory photostability. This may be a direct result of their better dispersion degree and their more gradual, controlled release from the EN during operation. If we compare the stabilizing effect of both polyphenols, quercetin was more efficient, which may be attributed to the presence of hydroxyl group at the C3 position in the C ring, which could increase the reactivity of the catechol structure of the B ring. The proposed approach effectively solves the issues that arise during the commonly used processing techniques and may facilitate the broader utilization of natural stabilizers in the polymer industry.
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DOI: 10.3144/expresspolymlett.2026.5
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DOI: 10.3144/expresspolymlett.2026.5

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DOI: 10.3144/expresspolymlett.2025.96
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DOI: 10.3144/expresspolymlett.2025.96

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DOI: 10.3144/expresspolymlett.2025.29
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DOI: 10.3144/expresspolymlett.2025.29

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DOI: 10.3144/expresspolymlett.2025.31

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DOI: 10.3144/expresspolymlett.2025.8
Vol. 19., No.1., Pages 107-121, 2025
DOI: 10.3144/expresspolymlett.2025.8

Biodegradable biopolymers like polyhydroxybutyrate (PHB) hold promise for sustainable packaging, but their inherent degradability reduces material stability. Synthetic stabilizers, though effective, raise environmental and potential toxicity concerns. This study explores a multifunctional natural anti-aging agent: a hemp extract rich in cannabidiol (CBD) and cannabichromene (CBC). PHB composites with varying hemp extract concentrations were prepared and subjected to thermooxidative and weathering aging. Characterization employed FTIR-ATR, carbonyl index, and spectrophotometry. Static mechanical properties, DSC, and surface free energy (SFE) were also assessed. Notably, the hemp extract exhibited stability under ambient conditions but showed migration with time and aging. The results suggest a plasticizing effect on PHB and highlight the contrasting roles of the extract: inhibiting thermooxidative aging while potentially accelerating aging under atmospheric conditions. This opens avenues for tailoring material durability, further evaluated by life cycle analysis (LCA). This work represents one of the first investigations into hemp extract as an anti-aging agent for eco-friendly polymers, expanding the knowledge base of natural multifunctional additives.



