fig24
From: Applications of flexible polyimide: barrier material, sensor material, and functional material
![Applications of flexible polyimide: barrier material, sensor material, and functional material](https://image.oaes.cc/20a85a8b-3151-4a16-8895-9df1ea8f96a1/5339.fig.24.jpg)
Figure 24. (A) Polyimide reacts with ammonia to form an amide; (B) the sensor of PMDA-ODA constructed on cotton fabric shows green color when there is no ammonia gas, and red color when there is ammonia gas resistance less than the threshold resistance[115].