A Novel PVDF Ultrafiltration Membrane Modified by C₆₀(OH)_n-Ag

Area of Science:

• Materials Science
• Membrane Technology
• Nanotechnology

Background:

• Ultrafiltration membranes require high permeability and resistance to fouling and bacterial contamination for water treatment and biomedical uses.
• Traditional polyvinylidene fluoride (PVDF) membranes often lack sufficient antibacterial and antifouling properties.
• Fullerol (C60(OH)n) offers hydrophilicity, while silver (Ag) provides bacteriostatic effects, suggesting potential for synergistic membrane enhancement.

Purpose of the Study:

• To prepare a novel fullerol-silver (C60(OH)n-Ag) complex as a multifunctional additive for ultrafiltration membranes.
• To fabricate and characterize polyvinylidene fluoride (PVDF) membranes composited with the C60(OH)n-Ag complex (C60(OH)n-Ag/PVDF).
• To evaluate the impact of the C60(OH)n-Ag additive on membrane permeability, retention, antifouling, and antibacterial properties.

Main Methods:

• A fullerol-silver (C60(OH)n-Ag) complex was synthesized utilizing the hydrophilicity of fullerol and the bacteriostatic properties of silver.
• The C60(OH)n-Ag complex was incorporated into a polyvinylidene fluoride (PVDF) matrix via immersion precipitation phase transformation to create C60(OH)n-Ag/PVDF membranes.
• Membrane performance was assessed by measuring water contact angle, pure water flux, bovine serum protein retention, flux recovery rate, and antibacterial activity against Escherichia coli and Staphylococcus aureus.

Main Results:

• The C60(OH)n-Ag/PVDF membrane exhibited significantly reduced surface water contact angle (34.50° vs. 75.05° for PVDF).
• Pure water flux increased substantially (804.05 L·m⁻²·h⁻¹ vs. 224.11 L·m⁻²·h⁻¹), and bovine serum protein retention improved (96.44% vs. 75.00%).
• The modified membrane demonstrated enhanced flux recovery (79.08% vs. 64.91%) and significant inhibition of Escherichia coli and Staphylococcus aureus, unlike the unmodified PVDF membrane.

Conclusions:

• The incorporation of the fullerol-silver (C60(OH)n-Ag) complex effectively enhances the performance of PVDF ultrafiltration membranes.
• The C60(OH)n-Ag/PVDF membranes possess improved hydrophilicity, permeability, retention, and antifouling capabilities.
• The developed membranes show promising antibacterial activity, making them suitable for advanced water treatment and biomedical applications.