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This study investigates the structural and functional enhancement of corn zein–chitosan composites via mild alkaline treatment to develop biodegradable protein-polysaccharide materials for diverse applications. Films with varying zein-to-chitosan ratios were fabricated and characterized using Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Both untreated and sodium hydroxide (NaOH)-treated films were evaluated to assess changes in physicochemical properties. FTIR analysis revealed that NaOH treatment promoted deprotonation of chitosan’s amine groups, partial removal of ionic residues, and increased deacetylation, collectively enhancing hydrogen bonding and resulting in a denser molecular network. Simultaneously, partial unfolding of zein’s α-helical structures improved conformational flexibility and strengthened interactions with chitosan. These molecular-level changes led to improved thermal stability, reduced degradation, and the development of porous microstructures. Controlled NaOH treatment thus provides an effective strategy to tailor the physicochemical properties of zein–chitosan composite films, supporting their potential in sustainable food packaging, wound healing, and drug delivery applications. 

Ion transport in solid polymer electrolytes is crucial for applications like energy conversion and storage, as well as carbon dioxide capture. However, most of the materials studied in this area are petroleum-based. Natural materials (biopolymers) have the potential to act as alternatives to petroleum-based products and, when derived with ionic liquid (IL) functionalities, present a sustainable alternative for conductive materials by offering tunable morphological, thermal, and mechanical properties. In this study, a series of IL-functionalized cellulose derivatives with variations in pendant alkyl chain length, counteranions, and degrees of substitution were synthesized in order to explore structure-property relationships. Emphasis was placed on investigating morphological, thermal, and ionic conductivity changes, hypothesizing that materials synthesized with longer alkyl chains would exhibit increased backbone-to-backbone spacing, thereby lowering the glass transition temperature, and enhancing ionic conductivity. A variety of characterization techniques were used for this investigation, including nuclear magnetic resonance spectroscopy (NMR), elemental analysis, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray scattering, and dielectric relaxation spectroscopy (DRS). The findings reveal a link between longer alkyl chain lengths, expanded backbone-backbone spacing, and side chain interdigitation. Within each set of samples, heightened ionic conductivity was observed with the introduction of bulkier, less coordinating anions, underscoring the significant influence of counteranion size. 

Polymers play a critical role in the biomedical and sustainable materials fields, serving as key resources for both research and product development. While synthetic and natural polymers are both widely used, synthetic polymers have traditionally dominated due to their ability to meet the specific material requirements of most fiber fabrication methods. However, synthetic polymers are derived from non-renewable resources, and their production raises environmental and health concerns. Natural polymers, on the other hand, are derived from renewable biological sources and include a subset known as biopolymers, such as proteins and polysaccharides, which are produced by living organisms. These biopolymers are naturally abundant and offer benefits such as biodegradability and non-toxicity, making them especially suitable for biomedical and green applications. Recently, air jet spinning has emerged as a promising method for fabricating biopolymer fibers, valued for its simplicity, cost-effectiveness, and safety—advantages that stand out compared to the more conventional electrospinning process. This review examines the methods and mechanisms of air jet spinning, drawing on empirical studies and practical insights to highlight its advantages over traditional fiber production techniques. By assembling natural biopolymers into micro- and nanofibers, this novel fabrication method demonstrates strong potential for targeted applications, including tissue engineering, drug delivery, air filtration, food packaging, and biosensing, utilizing various protein and polysaccharide sources. 

Abstract The synthesis and characterization of a series of polyurethane ionenes using a non‐isocyanate approach is disclosed. Imidazole‐capped, urethane‐containing prepolymers are prepared by first reacting carbonyl diimidazole (CDI) with several poly(propylene glycol) (PPG) diols with variable molecular weight, followed by subsequent reaction with 3‐aminopropylimidazole (API). Polymerization with 1,4‐dibromomethylbenzene followed by anion exchange resulted in the desired polyurethane ionenes bearing the [NTf₂] counteranion as a series of viscous liquids. NMR and FTIR spectroscopy are used to characterize the intermediates and final ionenes, including molecular weight determination by end‐group analysis. A single glass transition temperature (T_g), as determined by differential scanning calorimetry (DSC), is observed for each ionene (−38 to −64 °C) with theT_gdecreasing with increasing PPG molecular weight. Thermogravimetric analysis (TGA) indicated a two‐step decomposition for each ionene, with the first being degradation of the PPG segment, followed by the urethane/ionic segment. Microphase separation is observed from x‐ray scattering profiles with Bragg distances that increased with increasing PPG molecular weight. Ionic conductivity is found to be inversely dependent upon DSCT_gat lower temperatures (RT and below); however, at higher temperatures, conductivity appears to be more dependent upon the ability of ionic aggregates caused by phase separation to interact.