Preparation and characterization of biopolymer-based packaging materials have significantly gained importance because of sustainability, biodegradability, and eco-friendly nature. In this study, novel wheat gluten (WG)/cloisite 30B (C30B) organoclay-based bionanocomposite (BNC) films were prepared by solution casting method at various C30B concentrations (5%, 10%, and 15%). X-ray diffraction and field emission scanning electron microscopy revealed intercalation/exfoliation of C30B sheets into the WG matrix. WG-C30B 10% film was thermostable. It showed low surface roughness along with higher water barrier properties and surface hydrophobicity. The tensile strength values of WG and WG-C30B 10% films were found to be 0.7 +/- 0.02 and 1.11 +/- 0.01, respectively, indicating improvement in mechanical properties. WG-C30B 10% film demonstrated antibacterial activity against both Staphylococcus aureus and Salmonella enterica. Shelf life of green grapes was monitored under different conditions: 4 degrees C, ambient conditions, and 42 degrees C. WG-C30B 10% film proved effective in extending shelf life up to 18 days under ambient conditions. More than 50% of the bionanocomposite films were degraded in agricultural soil within 2 weeks, while completely degraded in sewage sludge soil after a few days. WG-C30B 10% film appeared to be promising regarding the demonstrated physico-chemical and antibacterial properties. This report would be useful in preparing biodegradable biopolymer-based packaging materials.

Fenton cellulose nanofibrils (F-CNF) were prepared by Fenton oxidation with the followed homogenization and then F-CNF /PVA composite films with the F-CNF additives from 1% to 20% were prepared by solution casting method. Scanning electron microscopy (SEM), confocal laser scanning microscope (CLSM), Fourier transform infrared spectroscopy (FTIR), universal tensile testing machine, swelling property detection, thermogravimetric analysis and soil burial degradation rate test were used to characterize the microstructure, chemical structure, mechanical properties, hygroscopicity, thermal stability and biodegradability of the composites. The results showed that a large number of hydrogen bonds were formed between F-CNF and PVA molecules and an acetal reaction occurred. F-CNF can be uniformly dispersed in PVA matrix, and both have good interfacial compatibility. After the addition of F-CNF, the tensile strength and elastic modulus of the composite films were significantly improved, the water absorption of the composite material was reduced, and its thermal stability was improved. When the amount of F-CNF was 15%, the tensile strength and Young's modulus of the composite films were 65.27 MPa and 1460.32 MPa, respectively, which were 217.77% and 830.69% higher than those of pure PVA.

Carboxymethyl cellulose (CMC) has attracted considerable interest in research due to its exceptional film-forming properties and compatibility with biological systems. However, CMC films still suffer from mechanical brittleness and structural instability due to the rigid structure and many hydroxyl groups in practical applications. Herein, a nanocomposite film is reported, synthesized via inserting layered montmorillonite (MMT) into a CMC and guar gum (GG) hydrogen bond networks. Incorporating MMT with a high aspect ratio increases the number of hydrogen bond cross-linking sites among constituents, thereby enhancing the mechanical strength and toughness of nanocomposite films. The resulting CMC/GG(10)/MMT6 films show flexibility (elongation at break 83.5 +/- 4.35%), high tensile strength (53.5 +/- 1.10 MPa), and high toughness (32.16 +/- 1.04 MJ/m(3)). These films also integrate hydrophobic (up to 84.78 degrees) and high-temperature resistance (50% degradation temperature up to 304 degrees C) properties to adapt to complex practical application environments. Moreover, they exhibit excellent ultraviolet shielding performance under a wide wavelength range (200-320 nm). Soil burial experiments showed that all the films could be assimilated into the soil within about 9 days. This approach offers a simple and promising route for producing biodegradable CMC-based films for food packaging.

Bio-based polymers are a promising material with which to tackle the use of disposable and non-degradable plastics in agriculture, such as mulching films. However, their poor mechanical properties and the high cost of biomaterials have hindered their widespread application. Hence, in this study, we improved polysaccharide-based films and enriched them with plant nutrients to make them suitable for mulching and fertilizing. Films were produced combining sodium carboxymethyl cellulose (CMC), chitosan (CS), and sodium alginate (SA) at different weight ratios with glycerol and CaCl2 as a plasticizer and crosslinker, respectively, and enriched with ammonium phosphate monobasic (NH4H2PO4). A polysaccharide weight ratio of 1:1 generated a film with a more crosslinked structure and a lower expanded network than that featuring the 17:3 ratio, whereas CaCl2 increased the films' water resistance, thermal stability, and strength characteristics, slowing the release rates of NH4+ and PO43-. Thus, composition and crosslinking proved crucial to obtaining promising films for soil mulching.

The proliferation of single-use plastics has led to widespread pollution and ecological harm, prompting a concerted effort to develop sustainable alternatives. Among them, biocomposite plastic films have emerged as a promising solution for food packing applications. Herein, the preparation of polyvinyl alcohol (PVA) biocomposite films incorporating Clitoria ternatea (CT) flower extracts is reported. The obtained films are subjected to various analytical techniques. Fourier transform infrared spectroscopy analysis reveals the intense peak of hydrogen bonding at 3321 cm(-1) in the composite film. CT-PVA films possess less opacity and UV light-blocking capabilities. The PVA-CT films are examined for water absorption, UV barrier, soil degradability, and water-soluble properties, greater propensity to dissolve in water during the water absorption test is noticed. Enzymatic oxidation followed by hydrolysis of functional groups enhances the soil degradation rate in biocomposite films. Further, the colorimetric study of CT-PVA solution at different pH shows colored CT-PVA films. From the results and observations, the CT-PVA biocomposite film (8 mL) proves to be a promising candidate for utilization in the food industry as a packaging material.

Food packaging films play a vital role in preserving and protecting food. However, due to their nonbiodegradability, conventional packaging materials have led to significant environmental pollution. To overcome this hurdle, we have developed safe, innovative, sustainable and biodegradable packaging materials that can effectively extend the shelf life of food. In this study, two types of cellulose materials cellulose nanofibers (CNF) and carboxymethyl cellulose (CMC) with complementary roles were combined to prepare nanocellulose composite films with high transparency (90.3 %) of a certain thickness (30 +/- 0.019 mu m) by solution casting method, and their mechanical properties were further optimized by the addition of plasticizer-glycerol (Gly) and cross-linking agent-glutaraldehyde (GA), so as to maintain the strong tensile strength (approximate to 112.60 MPa) and better malleability (4.12 %). In addition, we loaded the natural active agent tea polyphenols (TPs) with different concentrations to study the inhibition effect on E.coli and S.aureus and to simulate food packaging. Finally, we also found that the synthesized nanocellulose composite films can also achieve rapid degradation in a short time through soil burial, water flushing and immersion. The excellent performance demonstrated in this study provides reference value for further replacing petroleum-based materials with biomass materials in the field of food packaging.