Water-Triggered Dimensional Swelling of Cellulose Nanofibril Films: Instant Observation Using Optical Microscope

Figure 3

Microscopic cross-section images of CNF (top) and CNF/10% PF (bottom) films before (left) and after (right) being soaked in water for 5 min. The scale bars represent 200 μm.

(a)

(b)

(c)

(d)