WAITING
Search for articles
search


Research article
|
|
Quaternized cassava starch-based film reinforced by nanocrystalline cellulose with antimicrobial activity against bacteria and coronavirus
Guilherme Ribeiro de Carvalho, Rafael Affonso Netto, Camila Delarmelina, Marta Cristina Teixeira Duarte, Liliane Maria Ferrareso Lona
Vol. 19., No.7., Pages 686-696, 2025
DOI: 10.3144/expresspolymlett.2025.52
Corresponding author: Guilherme Ribeiro de Carvalho

GRAPHICAL ABSTRACT

ABSTRACT

In this study, a new plastic film with antiviral and antibacterial properties was developed using modified cassava starch with glycidyltrimethylammonium chloride (GTMAC) and reinforced by crystalline nanocellulose (CNC), called Q-CS/CNC. For comparison, a control film (Q-CS) was produced without the addition of CNC. Elemental analysis revealed a degree of substitution (DS) of 0.552, indicating the replacement of the OH groups of starch by the NR4+ groups of GTMAC during the quaternization reaction. The addition of CNC resulted in significant increases (p < 0.05) of 38.9, 38.2, and 43.1% in thickness, opacity, and water vapor permeability measurements, respectively, compared to Q-CS. Incorporating CNC also contributed to an increase of 43.6% in tensile strength and 109% in stiffness but slightly decreased thermal stability. The Q-CS/CNC film demonstrated efficacy by inactivating 99% of the coronavirus in 1 min and inhibiting the growth of Staphylococcus aureus and Escherichia coli. This action is attributed to the electrostatic interaction of quaternary amino groups, grafted onto starch, with the phospholipid membrane of microorganisms, resulting in the inactivation of these microorganisms. Therefore, these results highlight the potential use of Q-CS/CNC film as antimicrobial packaging, especially against coronavirus.


RELATED ARTICLES

Tailoring NIPUs: Exploring the role of various diacids in non-isocyanate polyurethane synthesis
Evangelia Balla, Panagiotis Klonos, Apostolos Kyritsis, Dimitrios Bikiaris
Vol. 20., No.2., Pages 154-167, 2026
DOI: 10.3144/expresspolymlett.2026.13
In recent decades, numerous efforts have been dedicated to the investigation of eco-friendly non-isocyanate polyurethanes (NIPUs) as alternatives to conventional polyurethanes (PUs). Since isocyanates are classified by the EU as hazardous and toxic compounds, NIPUs offer a promising route to mitigate isocyanate-related health risks as well as other environmental concerns associated with traditional PU synthesis. In the present study, we report the synthesis as well as the detailed structural and thermal characterization of a new series of fully biobased non-isocyanate polyurethanes (NIPUs) based on aliphatic dicarboxylic acids of different chain lengths. The NIPUs were prepared via a two-step polyaddition reaction involving glycerol carbonate and diamine. Their synthesis enables a sustainable pathway to tailor NIPUs’ physicochemical properties via diacid structure control. Studies of their structure, thermal behavior and trends, morphological, and hydrolytic findings confirmed strong diacid chain length dependence on glass transition temperature (Tg ~13, 0, ‒5 and –23 °C), molecular weight, surface wettability, and enzymatic degradability. Short-chain diacids yielded NIPUs with rapid hydrolytic degradation, while their longer-chain analogs were hydrophobic and thermally stable. Contact angle measurements (~75–85°) also confirm these trends. The tunable properties position these materials among strong candidates for biomedical applications.
Ultrasound-assisted green extraction of shrimp-waste chitosan for bioactive aerogel scaffolds
Soni Thakur, Amal M. Sindi, Rahul Dev Bairwan, Rasha A. Mahmoud, Eman Alfayez, Nurul Fazita Mohammad Rawi, Kanchan Jha, H.P.S. Abdul Khalil
Vol. 20., No.2., Pages 197-214, 2026
DOI: 10.3144/expresspolymlett.2026.16
This research presents an eco-friendly approach for extracting chitosan from shrimp shell waste through ultrasound-assisted extraction (UAE) to prepare biocompatible aerogel scaffolds for biomedical applications. The study investigates the influence of various ultrasonic treatment times (10, 20, 30, 40 min) on the yield and structural and physicochemical properties of the extracted chitosan via characterization using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Among the tested conditions, the 30 min UAE-treated chitosan aerogels showed optimal porosity and structural integrity. Biocompatibility of the aerogels was evaluated, and the results confirmed their non-cytotoxic nature. The bioactivity of the chitosan aerogels was evaluated in terms of their in vitro wound closure ability and antibacterial properties. The aerogels demonstrated a wound closure rate of around 51% after 72 h, significantly higher than the untreated control (37%). In addition, they exhibited clear antibacterial activity against Escherichia coli and Staphylococcus aureus. This sustainable extraction and fabrication method not only adds value to marine waste but also produces functional biomaterials with potential applications in wound healing, tissue engineering, and regenerative medicine, supporting global efforts toward sustainability and circular bioeconomy.
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
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.
Sustainable pineapple fiber-based PLA-PBAT biocomposites: Development, characterization, and analysis
Yashpal Singh, Raj Kumar, Nikhil Chauhan, Tejas Pramod Naik, Inderdeep Singh
Vol. 20., No.1., Pages 97-111, 2026
DOI: 10.3144/expresspolymlett.2026.8
The current experimental investigation presents a comparative evaluation of selected biodegradable polymer blends and their composites, focusing on their material properties. Two biopolymers, polylactic acid (PLA) and polybutylene adipate-co-terephthalate (PBAT), along with pineapple fibers (F), as bio-reinforcement were taken for the analysis, which was conducted in two stages: During first stage, PBAT was melt-blended with PLA in varying weight fractions (10, 20, 30, 40, and 50 wt%) to produce PLA/PBAT blend (B) and in second stage, PLA, PBAT, B 80/20 blend were reinforced with pineapple fiber (10, 20, and 30 wt%). The samples were fabricated using extrusion-injection molding. The samples were characterized for density, thermal degradation, crystallinity, and mechanical behaviour. Among the blends, the optimal B 80/20 combination exhibited tensile strength, flexural strength, and elongation at break of 47.9±2.4, 88.2±5.4 MPa, and 330.6±10.47%, respectively. Results indicate that the PLA-based composites (PF) exhibit significantly better density, tensile strength, and flexural strength as compared to neat polymers, blends, blend-based composites (BF), and PBAT-based composites (TF). Among the PF composites, the PF 70/30 composite demonstrated superior performance, with maximum tensile and flexural strength values of 73.9±1.3 and 107.1±4.3 MPa, respectively.
Production of bacterial cellulose by spontaneous fermentation of grape pomace and its thermal, mechanical, and spectroscopic characterization
Isabel Milagros Gavilan-Figari
Vol. 20., No.1., Pages 72-81, 2026
DOI: 10.3144/expresspolymlett.2026.6
Bacterial cellulose (BC) is an eco-friendly biopolymer with outstanding structural and functional properties, offering promising applications in sustainable packaging and bio-based materials. In this study, we demonstrate the feasibility of producing BC via spontaneous fermentation, using grape pomace supplemented with sucrose as the sole carbon source, nutrient substrate, and microbial inoculum, without the addition of commercial strains or nitrogen supplements. Fermentation was conducted under static conditions, yielding biofilms with stable structural characteristics and BC production of up to 14.1 g/L, thereby confirming the efficiency of this low-cost, residue-based process. The films obtained exhibited well-organized polymeric networks, with thermal stability in the range of Tg ≈ 159–266 °C and mechanical resistance comparable to or higher than conventional biopolymers. Characterization confirmed reproducible chemical profiles, thermal stability, and measurable variation in mechanical performance, with a tensile strength ranging from 0.0001 to 105 MPa and an elongation at break of 15±5%. The process highlights a resource-efficient and sustainable pathway, adaptable to rural contexts and aligned with circular economic principles. While minor variations among replicates reflected the intrinsic variability of biological systems, mean values and standard deviations demonstrated reproducible physicochemical and mechanical properties. These findings demonstrate that BC derived from agro-industrial residues can be produced under simple, low-input conditions, opening opportunities for scalable valorization in functional and sustainable materials.
Published by:

Budapest University of Technology and Economics,
Faculty of Mechanical Engineering, Department of Polymer Engineering