Effect of hyperbranched polyester and poly(amine ester) on the performance and properties of polyethersulfone membranes

Two different synthetic hyperbranched polymers (HBPs), a polyester and a poly(amine ester), were used as additives in the preparation of polyethersulfone (PES) membranes. Different compositions of polyethersulfone and hyperbranched polymers were dissolved in N -methylpyrrolidone and the membranes were prepared from dope solutions using a typical phase inversion method. Surface and cross-sectional morphology of the membranes were studied using scanning electron microscopy. Besides, accessible pore volume and surface hydrophilicity of membranes were determined by water uptake and contact angle measurements, respectively. The PES–HBP membranes showed enhanced hydrophilicity compared to neat PES ultrafiltration membrane. Time-dependent permeation studies revealed improved flux of PES–HBP membranes. Finally, modified membranes were subjected to bovine serum albumin protein rejection studies. Better fouling resistance was observed for PES–HBP blend membranes as compared to pristine PES ultrafiltration membrane. Interestingly, the two types of hyperbranched polymers showed similar effects, and both the permeation and antifouling properties of PES–HBP membranes were improved with increase in HBP content.