The gas barrier property of the GO/cellulose paper was studied by a determination of air permeability as shown in Fig. 4. Initially, the air permeability decreases sharply with the increase of GO content, and then the curve became flatter after the GO content was higher than 4 wt% while the decreasing trend was kept till the GO content reached 16 wt%. The smallest gas permeability 0.094 m/Pa s was obtained with 16 wt% GO contents, which decreased by 99.85% compare with pure cellu-losic paper (64.3 m/Pa · s). and this number is lower than thepaper (0.29 m/Pa s) surface-sized with 12.58 g/m2alkyl ketenedimer/nanocrystalline cellulose emulsion (Yang et al., 2016).The obviously reduced air permeability was probably due to