Benzoxazine/ thermoplastic polyurethane nanofibrous membranes with superior mechanical properties for efficient oil-water separation

Abstract

The integration of membrane separation and electrospinning technologies has significantly advanced oil-water separation processes. However, enhancing the mechanical robustness, corrosion resistance, and durability of oil-water separation membranes remains a challenge. In this paper, we utilized the electrospinning technique to fabricate a micro-nanostructured nanofibrous (NFs) membrane by blending benzophenone monomer (BPAF-an) with thermoplastic polyurethane elastomer (TPU). By optimizing the solid content, the mass ratio of compounds to polymers, and the solvent composition in the spinning precursor solution, we determined the optimal electrospinning parameters for fabricating the TPU/BPAF-an NFs membrane. The incorporation of BPAF-an, known for its low surface energy, significantly enhanced the hydrophobicity of the nanofiber membrane. The TPU/BPAF-an NFs membrane demonstrated excellent mechanical properties, exhibiting a tensile strength of 7.38 MPa and an elongation at break of 292 %. The membrane had good hydrophobicity and its water contact Angle is up to 145.2°. It also displayed exceptional separation efficiency, exceeding 99 % for oil-in-water emulsions and various oil-water mixtures. Even in harsh environments such as strong acids, alkalis and salts, they have prominent hydrophobicity, lipophilicity and chemical stability. In addition, the membrane maintained a high flux rate of 1995.37 L m−2 h−1 and a separation efficiency of 96 % even after 100 cycles of oil-water separation. Consequently, the TPU/BPAF-an NFs membrane, with its superior mechanical properties and cycle stability, holds substantial promise for application in oil-water separation.