The role of silver nanoparticles on mixed matrix Ag/Cellulose acetate asymmetric membranes

Mixed matrix asymmetric membranes were prepared by the addition of silver nanoparticles to cellulose acetate/acetone/formamide casting solutions with ratios acetone/formamide varying from 1.44 to 2.77 to prepare ultrafiltration/nanofiltration membranes covering a wide range of hydraulic permeabilities. Binding of the silver nanoparticles to the polymer matrix is revealed through comparison of the FTIR spectra of the cellulose acetate and the Ag/cellulose acetate membranes. In the later, there is a decrease of the ratio between the bands intensities at 2,000–2,500 cm 21. Membrane surface charge of the mixed matrix membranes varies with the pore size and pH,and when compared with cellulose acetate membranes there is a decrease of the negative surface charge densities. The silver nanoparticles in all mixed matrix membranes results in an enhancement of the hydraulic permeabilities, ranging from 10.8 kg m 22 h 21 bar 21 to 67.1 kg m 22 h 21 bar21. POLYM. COMPOS., 38:32–39, 2017. VC 2015 Society of Plastics Engineers.