This article proposes a strategy to prepare membranes that combine the network characteristics of micro/nanocellulose with grafted zwitterionic PCysMA to develop fully bio-based membranes with antifouling properties.

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Nanocellulose is known to act as a platform for the in-situ formation of metal oxide nanoparticles, where the multiple components of the resultant hybrids act synergistically toward specific applications. However, typical mineralization reactions require hydrothermal conditions or addition of further reducing agents. Herein, we demonstrate that carboxylated cellulose nanofibril-based films can spontaneously grow functional metal oxide nanoparticles during the adsorption of heavy metal ions from water, without the need of any further chemicals or temperature. Despite the apparent universality of this behavior with different metal ions, this work focuses on studying the in-situ formation of copper oxide nanoparticles on TOCNF films as well as the resultant hybrid films with improved functionality toward dye removal from water and antimicrobial activity. Using a combination of cutting-edge techniques (e.g., in-situ SAXS and QCMD) to systematically follow the nanoparticle formation on the nanocellulosic films in real time, we suggest a plausible mechanism of assembly. Our results confirm that carboxylated cellulose nanofibril films act as universal substrate for the formation of metal oxide nanoparticles, and thus hybrid nanomaterials, during metal ion adsorption processes. This phenomenon enables the upcycling of nanocellulosic materials through multistage applications, thus increasing its sustainability and efficiency in terms of an optimal use of resources.

Microporous (<2 nm) crystalline aluminosilicates in the form of zeolites offer a great potential as efficient adsorbents for atmospheric CO2 in the eminent battle against global warming and climate change. The processability of conventional zeolite powders is, however, poor, which limits their implementation in many applications, such as in gas filtration industrial systems. In this work, we overcome this issue through the preparation of hybrid foams using mesoporous/macroporous supporting materials based on the strong network properties of gelatin/nanocellulose, which can support ultrahigh loadings of silicalite-1, used as a model sorbent nanomaterial. We achieved up to 90 wt % of zeolite content and a microporous/mesoporous/macroporous hybrid material. The application of hybrid foams for selective CO2 sorption exhibits a linear relationship between the zeolite content and CO2 adsorption capacity and high selectivity over N2, where the gelatin/nanocellulose foam efficiently supports the zeolite crystals without apparently blocking their pores.

Low-concentration oil-in-water emulsions stabilized by cellulose nanofibrils (CNFs) extracted from primary plant cell wall materials are used to prepare thin biobased CNF–oil composite films by solvent casting. Flexible, transparent, and biodegradable composite films are obtained, with increased thermal stability (up to 300 °C) as the oil concentration increases. Examination of the microstructure demonstrates a clear dependency on the oil content, as a multilayered structure where the oil phase trapped between two layers of CNFs is appreciated at high oil concentrations. The embedded oil significantly influences the mechanical and wetting properties of the films, confirming their potential for use in packaging systems. Encapsulation of curcumin in the composite films leads to an increased antioxidant (up to 30% radical scavenging activity) and antimicrobial activity, inhibiting the growth of foodborne bacteria such as Escherichia coli. The resulting composite films show promising results in the field of active packaging for applications in the food, pharmaceutical, and cosmetic industries.

Rising sustainability demands the search of new low-market-value sources of lignocellulosic biomass as raw material for nanocellulose processing. In this paper, we accordingly propose the isolation of nanocellulose from Prosopis juliflora, an abundant but environmentally undesired tree. P. juliflora wood was powered, refined by steam explosion and bleaching, and subsequently used to isolate cellulose nanocrystals and nanofibers by means of acid hydrolysis and mechanical fibrillation. The derived nanocrystals had a rod-shaped structure with an average diameter of 20 nm and length of 150 nm, whereas the nanofibers had a diameter of 10 nm and length in micron size. Moreover, we report a simple method to isolate nanolignocellulose by using partially bleached P. juliflora as feedstock. The presence of lignin provided antioxidant and antimicrobial activity to nanocellulose, as well as hydrophobicity and increased thermal stability. The study demonstrates the successful use of P. juliflora to extract functional nanomaterials, which compensate for its environmental concern and declining market interest.

This article deals with the plasma-surface modification of cellulose nanocrystals and their employment as reinforcement additive of ABS.

In this work, we demonstrate a re-entrant transition of carboxylated cellulose nanofibrils hydrogel where the gel-strength abruptly increases and then decreases back upon monotonic increase in multivalent salt concentration.