Obviously, oleophobic surface is not yet beneficial for
developing an oil absorbent. Therefore, an appropriate amount,
i.e. a small amount of PFOTES in this study (treated for 1 s), is
enough to ensure a high oil absorbency. In addition for soybean
oil, PFOTES-CGF exhibits also a higher oil absorbency for engine
oil and kerosene, with the increase percentage of 52.2% for soybean
oil, 22.0% for engine oil and 112.2% for kerosene, respectively
(Fig. 3b). SEM observations reveal that after PFOTEs treatment, a
roughen surface can be formed to facilitate the retention of oils
absorbed into fiber assembly from escaping, resulting in remarkable
improvement in the oil absorbency