Development of low-biofouling polypropylene feedspacers for reverse osmosis

Microbial fouling, or biofouling, is the accumulation of microorganisms onto material surfaces. The goal of this project was to develop low-biofouling polypropylene (PP) films through the functionalization of PP by a spacer arm with metal chelating ligands charged with copper ions. Virgin and modified PP films were put in contact with 3.0 ×10 ⁵ Escherichia coli cells/mL solutions for periods of time varying from 24 to 168 h. Fourier transform infrared spectroscopy (FTIR) and x-ray energy dispersive spectroscopy (EDS) were used to verify the functionalization reactions and monitor copper leaching. Direct counts of cells stained with dsDNA showed, invariably, that the microbial attachment to the modified PP films was an order of magnitune lower than on the virgin PP. Further, over a period of time of 2 weeks, no significant amounts of copper leached from the low-biofouling PP films.