Figure 11.

The time sequence of the oil/water separation process with cellulose-g-PNIPAAm paper (a). The oil/water mixture is composed of oil (dyed by sudan (III)/water). The left and right insets show the water droplet (top) and the oil droplet (bottom) on the corresponding cellulose-g-PNIPAAm, which is a schematic description (b); a contrast oil-only/water-only liquid filtration with the cellulose-g-PNIPAAm paper at 25 °C and 50 °C, respectively (c); the molecular mechanism diagram of the cellulose-g-PNIPAAm paper’s thermal-responsive wettability. Cellulose forms the main structure of the paper, while the reversible formation of the intermolecular and intra-molecular hydrogen bonding of PNIPAAm below and above the Lower Critical Solution Temperature exhibit the thermally-responsive wettability of the paper (d).