PREPARATION OF POLYACRYLONITRILE ULTRAFILTRATION MEMBRANES FROM POLYMER-SOLUTIONS CONTAINING GLYCEROL

The conditions for the formation of ultrafiltration membranes based on polyacrylonitrile methylmetacrylate sodium vinylsulfonate have been studied. Glycerol is used as an additive in the casting solution with a concentration of 0.5-4 wt.%. The effect of glycerol content on the structure and pore-size distribution of the membranes have been studied. It is established that with an increase in the glycerol concentration in the casting solution, membranes with a higher pore density and with smaller pore size are formed and thus increase their selectivity with respect to lower molecular weight components. The selectivities for different calibrants such as trypsin, lyzozyme, cytochrome-c are reported. The flux with respect to the mentioned calibrant solutions is as high as 230-250 l/m2-hr. It has been established that the glycerol plays an important role in the formation of membrane structure, and leads to a better performance.