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In the work by Thi Thu Thao Ho et al. on page 638, composite films of nanofibrillated cellulose (NFC) and vermiculite are prepared and subsequently treated with liquid ammonia. Upon treatment, the crystal structure of cellulose both in the presence and absence of vermiculite changes from cellulose I to III. The structure of trimethylammonia-modified (TMA)-NFC/vermiculite films before and after ammonia treatment is the most dense and most homogeneous due to electrostatic attraction between ammonium groups of TMANFC and anionic layers of vermiculite. Treatment of composite films with ammonia leads to a significant decrease in water vapor permeation. Therefore, the composites have potential applications as eco-friendly barriers for food packaging. The cover is a SEM image of a TMA-NFC/vermiculite dried suspension (mass ratio = 1:1). Fine vermiculite platelets are found to distribute homogeneously in the cationic NFC network.