Superwettable PVDF/PVDF- g-PEGMA Ultrafiltration Membranes

Qidong Wu; Alberto Tiraferri; Tong Li; Wancen Xie; Haiqing Chang; Yuhua Bai; Baicang Liu

doi:10.1021/acsomega.0c03429

Superwettable PVDF/PVDF- g-PEGMA Ultrafiltration Membranes

ACS Omega. 2020 Sep 3;5(36):23450-23459. doi: 10.1021/acsomega.0c03429. eCollection 2020 Sep 15.

Authors

Qidong Wu¹, Alberto Tiraferri², Tong Li³, Wancen Xie¹, Haiqing Chang¹, Yuhua Bai⁴, Baicang Liu¹

Affiliations

¹ Key Laboratory of Deep Earth Science and Engineering (Ministry of Education), College of Architecture and Environment, Institute of New Energy and Low-Carbon Technology, Sichuan University, Chengdu, Sichuan 610207, P. R. China.
² Department of Environment, Land and Infrastructure Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.
³ Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay, Guangzhou University, Guangzhou 510006, P. R. China.
⁴ Infrastructure Construction Department, Chengdu University, Chengdu, Sichuan 610106, P. R. China.

Abstract

Poly(vinylidene fluoride) (PVDF) is a common and inexpensive polymeric material used for membrane fabrication, but the inherent hydrophobicity of this polymer induces severe membranes fouling, which limits its applications and further developments. Herein, we prepared superwettable PVDF membranes by selecting suitable polymer concentration and blending with PVDF-graft-poly(ethylene glycol) methyl ether methacrylate (PVDF-g-PEGMA). This fascinating interfacial phenomenon causes the contact angle of water droplets to drop from the initial value of over 70° to virtually 0° in 0.5 s for the best fabricated membrane. The wetting properties of the membranes were studied by calculating the surface free energy by surface thermodynamic analysis, by evaluating the peak height ratio from Raman spectra, and other surface characterization methods. The superwettability phenomenon is the result of the synergetic effects of high surface free energy, the Wenzel model of wetting, and the crystalline phase of PVDF. Besides superwettability, the PVDF/PVDF-g-PEGMA membranes show great improvements in flux performance, sodium alginate (SA) rejection, and flux recovery upon fouling.