A single biopolymer film rarely has a competitive edge against synthetic films. One solution is to combine several layers with different properties into multilayer structures. In this way, for example, the barrier properties of bio‐based materials can be improved. In this study, the multilayer films are produced by combining three different techniques/materials: 1) dispersion coating (cellulose nanofibrils, CNF), 2) atomic layer deposition (Al2O3; aluminum oxide), and 3) extrusion coating (polyglycolic acid, PGA). Especially the CNF and PGA‐containing multilayer films show promising oxygen barrier improvements at different humidities. Thin inorganic coatings are brittle and sensitive toward stresses during converting, which may limit their use in such specific multilayer structures. The developed bio‐based films largely fulfill the barrier requirements of fresh food packaging. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42260.

The aim of this study was to evaluate a thin, TEMPO‐oxidized (2,2,6,6‐tetramethylpiperidine‐1‐oxyl–mediated oxidation) cellulose nanofibril (CNF) coating as a barrier layer in multilayer packaging films together with biobased polyethylenes. The purpose was also to explore the possible interactions between food products and the biobased films, and to evaluate the feasibility of these films for packaging of dry foods. CNF provided the biobased multilayer films with an oxygen barrier suitable for both demanding food products and modified atmosphere packaging (MAP). The MAP pouches made of these multilayer films retained their atmosphere and shape and protected ground hazelnuts from further oxidation for the storage time used in this study. However, irradiation used to sterilize packed foods and aroma compounds from clove in particular impaired the oxygen barrier property of the CNF layer, while the water vapor barrier property of the multilayer films remained unaffected. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44830.

Technical and hygienic nonwovens, originating typically from fossil‐based synthetic polymers, are the fastest growing applications in the textile industry. Recently developed thermoplastic cellulose fatty acid esters have polyolefin like rheology properties and therefore the suitability of these cellulose esters for fiber production was evaluated. In this study, the melt spinning of textile fibers has been demonstrated using thermoplastic cellulose octanoate. The mechanical properties of melt spun fibers were analyzed by using tensile testing and both the surface and cross‐section morphology of melt spun fibers were studied using the scanning electron microscopy. The surfaces of the fibers were very smooth and also the cross‐section was very uniform and no porosity was observed. While mechanical properties of the produced fibers are not yet as good as those reported for commercial polypropylene (PP) monofilament fibers, they are somewhat more comparable to other cellulose ester‐based fibers. The melt spinning results indicate that the novel cellulose‐based fibers can provide a renewable and recyclable alternative, for example, spun‐laid PP in several hygienic textile and fully oriented in technical applications in future.

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Polymer foams are widely used in several fields such as thermal insulation, acoustics, automotive, and packaging. The most widely used polymer foams are made of polyurethane, polystyrene, and polyethylene but environmental awareness is boosting interest towards alternative bio-based materials. In this study, the suitability of bio-based thermoplastic cellulose palmitate for extrusion foaming was studied. Isobutane, carbon dioxide (CO2), and nitrogen (N2) were tested as blowing agents in different concentrations. Each of them enabled cellulose palmitate foam formation. Isobutane foams exhibited the lowest density with the largest average cell size and nitrogen foams indicated most uniform cell morphology. The effect of die temperature on foamability was further studied with isobutane (3 wt%) as a blowing agent. Die temperature had a relatively low impact on foam density and the differences were mainly encountered with regard to surface quality and cell size distribution. This study demonstrates that cellulose palmitate can be foamed but to produce foams with greater quality, the material homogeneity needs to be improved and researched further.