Rational Design of Polysulfone-based Polymeric Membranes for Water Treatment
Guan Li
Nowadays, the problem of water pollution is seriously threatening the existence of our human beings. In the past a few decades, membranes have been proved as an effective way for water treatment. Among all the materials, polymers with excellent physical properties, for example, polysulfone can be viewed as a good candidate to fabricate membranes. Unfortunately, membrane made from polysulfone alone yielded low water fluxes due to its inherently hydrophobic property, which seriously hinders its application in the water treatment field.
With the aim to tackle this problem, previous work in our group suggests that the addition of hydrophilic functional group such as carboxylic acid group onto the polysulfone backbone can improve membrane permeability through facilitating the process of water transport and the hydrophilic degree of carboxylated polysulfone along with the site of carboxylic acid group on the polysulfone backbone can be tuned as well. Then, two methods are employed to introduce copper and silver ions to membranes to greatly enhance the anti-bacterial performance of membrane without significantly losing the water flux performance.
Finally, besides simply introducing the anti-bacterial ions to the membrane, a facile and effective approach is further adopted to graft side chain with varying length to membrane via activating the carboxylic acid group to elevate the bacterial-repelling capability of membrane, which is followed by immersing our prepared side chain grafted membranes into aqueous solution containing copper and silver ions to bestow our membranes both anti-bacterial and anti-biofouling abilities