Fig. 5. Micrographs of different behaviour of water and oil droplets on the surfaces of (A and B) PDMS and (C and D) PDMS-Luffa sponges along with their corresponding contact angle images in the insets. Water forms a clear droplet on PDMS with contact angle of 112° (A) and PDMS-Luffa sponge with contact angle of 86° (B). The oil gets spread and absorbed on both PDMS with contact angle of 35° (C) and PDMS-Luffa sponge with contact angle of 68° (D).
