The establishment of self-healing polyethersulfone ultrafiltration membrane by host-guest interaction between the cucurbit[8]uril and objects

Abstract

Damage to ultrafiltration membrane during cleaning and the running of the process is known to lead to adverse loss of membrane integrity. Membranes with self-healing property will contribute to solve this problem, bypassing the need for real-time membrane integrity monitoring and replacing membrane frequently. Therefore, this study established the surface modified self-healing ultrafiltration membrane by interaction through cucurbit[8]uril (CB[8]) subject and objects. CB[8], PVA-MV and P(DMAEMA-r-NpMA) were employed as self-healing polymers to construct a self-healing layer on PES membrane surface through schiff base reaction and host-guest interaction. The comparison of permeability before and after membrane damage proved the effectiveness of membrane self-healing property. Furthermore, carbonyl groups with negative charge on CB[8] port and the hydrophilic groups in two guests gave the membrane hydrophilicity after that promoted the anti-pollution property of the membrane. The obtained membrane also showed excellent hydrophilicity, permeability and anti-pollution property, for example, the pure water flux of MPES-CB[8]0.15 reached to 1800.2 L/m2h, while BSA rejection rate could also be maintained at 89 %. The self-healing membrane MPES-CB[8]0.15 displayed a better FRR (89.1 %) compared with pure PES membrane, and the decrease of Rir (19.4 %) of MPES-CB[8]0.15 indicated that the adsorption of BSA was avoided. In a word, the self-healing membrane could not only solve the problem of loss of membrane integrity, but also improve comprehensive performance of membrane, such as hydrophilicity, permeability, thermal stability and mechanical properties.