of their colloidal stability, mechanical strength, high specific surface area, and thermal stability, [2][3][4][5][6] which have been used to produce transparent paper, biodegradable packaging, complex aerogels, and as the reinforcing phase in composites. [2,4,7,8] Despite all of its beneficial properties, cellulose exhibits poor flame resistance and gas barrier properties. [9,10] Improved barrier, mechanical, and flame resistant properties have been reported when montmorillonite clay (MMT) is used as a reinforcing agent in cellulose-based films. [11][12][13] The performance of polymer-clay barrier films is determined primarily by the clay characteristics (e.g., aspect ratio and density) and dispersion properties (i.e., clay exfoliation and orientation). For cellulose/clay composites, different methods to increase the interaction between clay and cellulose have been reported, including TEMPO-oxidation and by adding poly(vinyl alcohol) or chitosan (CH) as a compatibilizer. [14][15][16] Recently, cationic CNF with a quaternary ammonium functionality has been reported. [17] It was shown that the ionic interaction between the cationic CNF and MMT results in better mechanical properties of the composite, but further improvement is limited due to the formation of nanovoids as well as relatively low clay loading. [12,18] Layer-by-layer (LbL) assembly is a nanocoating technique that has been used to construct functional thin films for gas barrier and gas separation coatings, [19,20] energy storage and conversion, [21,22] drug delivery, [23] and adhesives. [24] By alternately depositing oppositely charged polyelectrolytes and/or clay platelets onto a charged substrate, thin films are assembled with high clay concentration and alignment. [25] In the present study, multilayer films consisting of anionic vermiculite (VMT) clay, with a high aspect ratio (≈2000), and cationic cellulose nanofibrils were investigated. This unique combination of highly aligned VMT platelets and cellulose nanofibrils forms a nanobrick wall structure with high transparency, excellent oxygen barrier, and fire resistance (superior to any other cellulose-based film previously reported). A 20 bilayer (BL) CNF/VMT nanocoating, with a thickness of 136 nm, exhibits a low oxygen transmission rate (OTR) of 0.013 cc (m 2 day atm) -1 . With only 2 BL of CNF/VMT, the melting of flexible polyurethane (PU) foam is prevented when exposed to a butane torch flame. These nanocoatings also exhibit high elastic modulus Cellulose nanofibrils (CNF) are abundant in the fiber cell walls of many plants and are considered a nearly inexhaustible resource. With the goal of improving the flame resistance and gas barrier properties of cellulose-based films, cationic CNF are assembled with anionic vermiculite (VMT) clay using the layer-by-layer deposition process. The highly aligned VMT nanoplatelets, together with cellulose nanofibrils, form a nanobrick wall structure that exhibits high optical transparency, flame resistance, super oxygen barrier, and high modulus. A 20 CNF/VMT...

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The present study attempted to examine the impact of inhabitants’ perceptions and local community participation on supporting sustainable tourism development. The goal of the current study was to determine how local community involvement and local views affected the development of a sustainable tourism industry. Inhabitants’ positive/negative perceptions and local community participation had direct but differential effects on supporting sustainable tourism development. Findings revealed that positive perceptions of residents affected their support for tourism development at twice the rate than their negative perceptions did, which indicated their higher readiness for participating in the tourism development process. Moreover, findings showed that using 16 latent variables to form a structural model and a path analysis method was good enough in terms of covering the research questions and analyzing the dataset.