Activated Carbon Effects on Morphology and Permeability of Poly(L-lactic acid)-Poly(ethylene glycol)Membranes

Poly(lactic acid) (PLA) is a bio-based polymer from plant resources and has been demonstratedto form porous, hydrophilicand strongstructure when copolymerized with poly(ethyleneglycol) (PEG). Thin film based on PLLA-PEG polyurethane copolymer hasaninterestingpotential application asadisposable biodegradable water filtration membrane.This study aimsto develop PLA-PEG polyurethane copolymer thin film membrane with a series of activatedcarbon (AC) contents of 2, 4, 6, 8,and 10 wt.%. Membrane matrix was first synthesized viachain extension reaction of dihydroxylterminated PLLA and PEG prepolymers withhexamethylene diisocyanate, beforetheaddition of AC, followed by membrane fabrication.Combining PLLA-PEG with AC resulted in changes in the morphology, thermal properties,and permeability of the membrane. Formation of urethane groups was observed intheATR-FTIR spectrum based on the appearance ofanew peak at 1619 cm−1corresponding to-NH-group. FESEM analysis showed that membrane with 6% AC hadmore uniform porescompared to membranes with 2% and 10% AC. Permeation water flux test demonstrated thatexerted pressure gave insignificant effect towards the resistance of membrane water fluxes,with the increment of AC resulted in increasing resistance. It was also found that the membranewith 2% AC hadthe highest total mean in permeation water flux, followed by 6% and 10%AC.