Highly stretchable and biodegradable superamphiphobic membrane for antifouling

Solvent evaporation-induced phase separation and fluorinated segment migration are the major reasons for the formation of hierarchical porous surface. The introduction of fluorinated segments (PTFOA) greatly improved the superhydrophobic and mechanical properties of the nanofibrous membrane. The superamphiphobic nanofibrous membrane could repel various solutions, including water, acidic, alkaline, coffee, glycol and n-hexane solutions. These solutions were repelled with a small sliding angle of water due to the membrane’s hierarchical pored morphology and low-surface-energy material, as revealed by scanning electron microscopy (SEM), atomic force microscopy (AFM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS) analyses.

Excellent enzymatic degradation

Studies of tensile testing and enzymatic biodegradation were also performed. The simultaneous reinforcing and toughening effect was achieved by the bonding of PTFOA onto the PCL chains, which breaking elongation increases from 152.97 %–678.15 %, and the tensile strength increases from 4.11 to 5.78 MPa. Additionally, the superamphiphobicity of the membrane was not lost with a strain up to 600 %. More importantly, the PCL-b-PTFOA nanofibrous membranes demonstrated excellent enzymatic degradation with 81.1 % weight loss at 37 °C for 24 h with Aspergillus oryzae in a phosphate buffer solution. These results suggest that compared with non-degradable materials, the prepared PCL-b-PTFOA nanofibrous membrane can be used as an excellent biodegradable material with good adaptability for antifouling and self-cleaning.

The study has been published in Progress in Organic Coatings, Volume 147, October 2020.