Sustainable packaging: A comparative study on thermoplastic whey protein films with biodegradable plasticizers
Forough Abbasi Shahir, Zahed Ahmadi
, Sayed Mahmood Rezaee Darvishi
, Sayed Mahmood Rezaee Darvishi Vol. 18., No.6., Pages 592-606, 2024
DOI: 10.3144/expresspolymlett.2024.44
DOI: 10.3144/expresspolymlett.2024.44
Corresponding author: Zahed Ahmadi 
GRAPHICAL ABSTRACT
ABSTRACT
Glyceryl lactate (GlyLA) was synthesized through the esterification of glycerol (Gly) and lactic acid (LA) to plasticize whey protein concentrate (WPC) films with three different ratios of WPC to plasticizer (85, 90, and 100% w/w). LA was also introduced as a new plasticizer of whey protein films and compared in similar contents. Gly-plasticized films were also used as control groups. The synthesized GlyLA, including compatible esterification degree with WPC, was characterized by Fourier transform infrared Spectroscopy (FTIR) and hydrogen nuclear magnetic resonance spectroscopy (H-NMR) analyses. Then, the plasticizing effect of different types of plasticizers on the optical, thermal, mechanical, and water resistivity properties of the prepared films was evaluated. FTIR in attenuated total reflectance (ATR), Differential Scanning Calorimetry (DSC), tensile measurements, and cup method were also employed to examine the molecular structure, transition temperatures, mechanical resistivity, and water vapor permeability (WVP) of the modified films. The results showed a lower glasstransition temperature (Tg) and better ductility. By Increasing plasticizer content, solubility and WVP were increased in all groups. Furthermore, WPC-based films plasticized with 80 or 90% w/w of LA and GlyLA exhibited not only higher tensile strength and flexibility but also remarkably lower WVP than Gly plasticized films, turning them into potential alternatives for application as food packaging.
RELATED ARTICLES
Yi-jie Yang, Qiang Dou
Vol. 20., No.4., Pages 349-370, 2026
DOI: 10.3144/expresspolymlett.2026.28
Vol. 20., No.4., Pages 349-370, 2026
DOI: 10.3144/expresspolymlett.2026.28
Poly(lactic acid) (PLA) has attracted much attention and shows promising applications in numerous fields. In this study, PLA was plasticized using bio-based castor oil derivatives - hydrogenated castor oil (HCO) and castor oil glycidyl ether (COGE). These eco-blends were measured using a Fourier transform infrared spectrometer, a scanning electron microscope, a contact angle test, rheology, a differential scanning calorimeter, thermogravimetry, polarized optical microscopy, and a tensile test, respectively. The findings show that a core-shell morphology of COGE-HCO encapsulation is formed in PLA matrix, and the hydrogen bonding interaction and ring-opening chemical reaction among functional groups of the components greatly improve the compatibility, ductility, cold crystallization ability, and thermostability of the eco-blends, but the melt crystallization ability is hindered. The incorporation of HCO improves the hydrophobicity and oleophobicity of the eco-blends. Due to the combined effect of HCO and COGE, the melt viscosity reduces, and the Newtonian behavior enhances; the nucleation density and spherulitic growth of PLA increase. The strain at break of the PLA/HCO/COGE (90/7.5/2.5) blend reached 221%, which is 22.6 times higher than that of the neat PLA. These eco-blends present appropriate rheological, thermal, and mechanical properties, showing application scenarios in biodegradable packaging and disposable appliances.
Narayanapura Mahadevappa Tanuja, Sommenahalli Machegowda Chaithra, Chikkahalkur Shivanandappa Kaliprasad, Mangaravalli Hombalegowda Harshitha, Shivapura Manchaiah Anush, Kalappa Prashantha
Vol. 20., No.1., Pages 36-51, 2026
DOI: 10.3144/expresspolymlett.2026.4
Vol. 20., No.1., Pages 36-51, 2026
DOI: 10.3144/expresspolymlett.2026.4
In this work, we have developed a novel absorbent material using chitosan (CS), and further it was structurally modified via reaction with thiocarbaldehyde, forming a Schiff base intermediate. Simultaneously, graphene oxide was functionalized at the C-6 position of CS through an effective esterification process and composited with the incorporation of molybdenum disulfide (MoS2) nanoparticles to synthesize a hybrid adsorbent material. The resulting material was characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The synthesized adsorbent was subjected to the adsorptive removal of Cu(II) and Cr(VI) ions from dilute solutions. The maximum uptake of 66.66 mg/g for Cu(II) and 76.92 mg/g for Cr(VI) were recorded during the adsorption process, further following pseudo-second-order kinetics adsorptive nature and fitted well with the Langmuir isotherm model. Desorption studies indicated the material’s reusability, and the thermodynamic studies indicated a spontaneity with an endothermic adsorptive nature. These studies highlight the material’s potential as an effective adsorbent as a sustainable approach for efficient environmental remediation.
Katalin Litauszki, Tamás Tábi, László Mészáros
Vol. 19., No.5., Pages 455-456, 2025
DOI: 10.3144/expresspolymlett.2025.33
Vol. 19., No.5., Pages 455-456, 2025
DOI: 10.3144/expresspolymlett.2025.33
This is an editorial article. It has no abstract.
Konrad Stefaniak, Anna Masek
Vol. 19., No.4., Pages 386-408, 2025
DOI: 10.3144/expresspolymlett.2025.29
Vol. 19., No.4., Pages 386-408, 2025
DOI: 10.3144/expresspolymlett.2025.29
This review is focused on recent achievements in poly(lactic acid) (PLA) synthesis and copolymerization with special regard to biotechnological routes of PLA synthesis, which use bacteria/enzymes (e.g., enzymatic ring opening polymerization (eROP)). Besides PLA, also lactic acid (LA) synthesis is described and an emphasis is put on the biotechnological methods. Having regard to PLA copolymerization, this paper attempts to describe different types of PLA copolymers (such as block copolymers, PLA copolymers with polysaccharides, PLA-cellulose copolymer composites, and PLA polymer brushes). A detailed overview of the recent accomplishments in the field of PLA copolymers is presented. Various enhanced properties and applications of presented PLA copolymers are discussed. The attention is placed mainly on applications in the field of tissue engineering, drug delivery systems, and the packaging sector. Furthermore, a PLA market study and its economic forecast are presented. Eventually possible directions for future research in the field of PLA synthesis and copolymerization are indicated.
Mohammad Mehdi Alighanbari, Firoozeh Danafar, Araam Namjoo, Asma Saeed
Vol. 19., No.1., Pages 15-46, 2025
DOI: 10.3144/expresspolymlett.2025.3
Vol. 19., No.1., Pages 15-46, 2025
DOI: 10.3144/expresspolymlett.2025.3
The environmental and ecological concerns drive researchers to synthesize functional materials using components from natural resources. Nanocellulose (NC), derived from plants, marine animals, or microorganisms, is a green material attracting attention due to its abundance, biocompatibility, and biodegradability. NC’s interstice properties enable the synthesis of functional nanocomposites in forms like aerogels, foams, paper, sheets, or hollow filaments. This review briefly describes NC classification and production while comprehensively presenting its mechanical, rheological, optical, and electrical properties, offering foundational knowledge for future research. Additionally, it highlights recent developments in NC-based products across fields such as papermaking, water treatment, civil engineering, electronics, cosmetics, food, and medicine. For the first time, this paper explores recent advances in NC molecular simulation, providing insights into structure, arrangement, and interactions through molecular dynamic simulation. Finally, future prospects for NC-based applications are discussed to encourage studies addressing current challenges.
