Improving Oxygen Barrier Properties in Fiber-Based F&B Packaging

Nanocelluloses are promising high gas barrier materials for biobased food packaging, but they must be protected from water to preserve high performance. The respective O2 barrier properties of different types of nanocelluloses were compared (nanofibers (CNF), oxidized nanofibers (CNF TEMPO) and nanocrystals (CNC)). The oxygen barrier performance for all types of nanocelluloses was similarly high. To protect the nanocellulose films from water, a multilayer material architecture was used with poly(lactide) (PLA) on the outside. To achieve this, a biobased tie layer was developed, using Corona treatment and chitosan. This allowed thin film coating with nanocellulose layers between 60 and 440 nm thickness. AFM images treated with Fast Fourier Transform showed the formation of locally-oriented CNC layers on the film. Coated PLA(CNC) films performed better (3.2 10-20 m3.m/m2.s.Pa) than PLA(CNF) and PLA(CNF TEMPO) (1.1 10-19 at best), because thicker layers could be obtained. The oxygen barrier properties were constant during successive measurements at 0 % RH, 80 % RH and again at 0 % R... Read More

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Many food products are sensitive to oxygen which can promote rancidity, aerobic microorganism growth, browning, vitamin degradation, flavor loss, and other undesirable reactions. Active packaging concepts have been successfully applied to delay these deteriorative phenomena. In particular, oxygen scavengers help limit O 2 ingress into packaging thus extending product shelf-life and thereby reducing food waste. Besides oxygen barrier polymers, other composite materials have been developed to reduce the overall O 2 permeability into the package by adding oxygen scavengers or barrier fillers into the packaging structures. Typical thermoplastic food packaging barrier properties are summarized, including commercially available ones, and reported in the patent literature. Furthermore, various mathematical models have been developed to predict the oxygen transport behavior in active packaging to simulate oxygen transport in polymeric and composite materials. Such models are helpful to provide a better understanding of the mass transport fundamentals involved and shorten product development ... Read More

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Recently, packaging industry has turned to biodegradable packaging, and poly(lactic acid) has become the most remarkable polymer. However, the high oxygen permeability of PLA films significantly limits their use. Therefore, this study, it was aimed to improve the oxygen barrier properties of PLA films without adversely affecting the mechanical and water vapor barrier properties. Biodegradable PLA-Zein bi-layer films were produced by changing PLA and zein thickness. Transparent and UV barrier bi-layer films were obtained. Mechanical properties of PLA films were improved by the production of bi-layer films. Water vapor permeability of bi-layer films increased whereas the permeance decreased with zein coating of PLA. Multi-criteria decision hierarchy was used to select the best bi-layer films based on mechanical, permeance, and opacity results. Oxygen barrier properties of PLA film significantly improved by zein coating, and hydrophobicity of PLA film was not affected by zein coating. The crystallization and melting temperatures of films decreased when compared to PLA films, supporting ... Read More

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Oxygen-selective perovskite hollow fiber membrane can be used to obtain an effective oxygen separation from air at high temperature (above 700 C) for large scale application. Here, we display that oxygen permeation fluxes of La0.6Sr0.4CoO3 (LSC113) hollow fiber membrane was enhanced by macrostructure modification and (La,Sr)2CoO4 (LSC214) surface decoration. By changing the cross-section macrostructure from sandwich structure (for LSC-a fiber) to asymmetric structure (for LSC-b fiber), the oxygen flux was improved by up to 3.6-fold. Applying porous LSC214 decoration on LSC113 furthermore enhanced the oxygen fluxes for LSC-a and LSC-b, by up to 6.8-fold and 1.9-fold, respectively.

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There are available reports on the barrier properties of composites; however, with highly focused research in this field, there is a need to reevaluate the findings and current trends. Hybrid composites are a mixture of inorganic and organic components at the nanometer or molecular level, whereas, biocomposites are formed by reinforcing natural fibers into a matrix to improve their properties, including barrier characteristics. Such composites can be used for many applications, including packaging, to maintain the quality of products. Thus, the barrier properties of films are important characteristics. This chapter discusses the parameters that influence the barrier properties of composites such as the pore size, chemical structure, free volume, and crystallinity of the polymer. The aims of this chapter are to provide comprehensive knowledge about factors affecting the permeability and preparation methodology, the types of composites, and the types of barrier characteristics including oxygen, carbon dioxide, water vapor, and aroma, and to present the potential applications of such hy... Read More

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Oxygen barrier coatings have the potential to greatly extend the lifetime of certain food products by incorporating them into existing food packaging. Present technologies face definite challenges of maintaining high performance, while attaining simple and inexpensive preparation methods. The oxygen barrier effect obtained with these coatings is also susceptible to a plasticization effect when exposed to high humidity, since water vapor molecules are readily soluble in typically hydrophilic resins. In this work, we demonstrate a 1 2 micron thick oxygen barrier coating, prepared on a 12 micron poly(ethylene terephthalate) substrate, that has oxygen transmission rates as low as 1.44 cc m-2 day-1 under standard conditions and can maintain similar oxygen barrier performance at high humidity. This degree of oxygen barrier meets the standard of 1 10 cc m-2 day-1 established for food packaging applications. The coating is prepared through use of sol-gel chemistry between poly(vinyl alcohol) and vinyltrimethoxsilane molecules, which form a strong network resin through hydrolysis and cond... Read More

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Multilayer container for food packaging that combines excellent oxygen barrier properties with improved heat pasteurization performance. The container features a unique gas barrier layer comprising an oxygen permeability resin, an oxygen absorptive adhesion layer, and an oxygen penetration layer. The gas barrier layer is integrated into the container's structure through a specialized manufacturing process that creates a continuous oxygen barrier layer throughout the thickness of the container. This approach eliminates the need for separate oxygen barrier layers, achieving superior oxygen barrier properties while maintaining the container's structural integrity. The container also incorporates an oxygen absorptive adhesion layer containing a deoxidizer component and thermoplastic resin, ensuring effective oxygen absorption during the packaging process.

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Fiber-based packaging materials have a need for barrier coatings to protect the packaged item from oxygen and contaminants to increase its shelf life. The material should preferably be from renewab ...

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In this paper, oxygen dielectric barrier discharge (oxy-DBD) plasma was employed to modify PBO fibers and enhance the interfacial adhesion of PBO fiber/bismaleimide composites. The interlaminar shear strength (ILSS) of the composites was improved greatly to 62.0 MPa with an increment of 41.2% at 30 W/cm3, 24 s. The SEM images of fracture morphology indicated that the failure place shifted from the interface to the matrix, and the water absorption decreased from 1.96 to 1.53%, the two results demonstrated the improved adhesive strength in other ways. In addition, the ILSS retention ratio of PBO/BMI composites after boiling in water were about 90%, confirming good humid resistance of the composites. The results obtained from XPS and AFM revealed that some polar groups were introduced onto PBO fibers and the surface morphology of PBO fibers was roughened. As a result, the wettability, reactivity and roughness of PBO fibers were all improved, they contributed to the improvement of the ILSS of the composites. The comparisons with air-DBD plasma showed that the chemical changes of PBO fibe... Read More

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The interface of fibrous composites is a key factor to the whole properties of the composites. In this study, the effects of air dielectric barrier discharge (DBD) plasma discharge power density on surface properties of poly( p phenylene benzobisoxazole) (PBO) fiber and the interfacial adhesion of PBO fiber reinforced poly(phthalazinone ether sulfone ketone) (PPESK) composite were investigated by several characterization methods, including XPS, SEM, signal fiber tensile strength, interlaminar shear strength, and water absorption. After the air DBD plasma treatment at a power density of 41.4 W/cm 3 , XPS analysis showed that some polar functional groups were introduced on the PBO fiber surface, especially the emergence of a new oxygencontaining group (OC = O group). SEM observations revealed that the air DBD plasma treatment had a great influence on surface morphologies of the PBO fiber, while the signal fiber tensile strength results showed only a small decline of 5.9% for the plasmatreated fiber. Meanwhile, interlaminar shear strength value of PBO/PPESK composite was increased ... Read More

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