The Effect of Hydrophilization of Polypropylene Membranes with Alcohols on Their Transport Properties

Abstract

ABSTRACT The effect of alcohol alkyl chain length on hydrophobic character of polypropylene (PP) membranes has been studied. The polypropylene membranes hydrophilized with methyl, ethyl, n-propyl and n-butyl alcohol were used in the studies. The studies were carried out by the impedance method and the changes in transport properties of the studied membranes at various hydrophilizing agent concen-trations were estimated. The polypropylene membranes were found to be firmly hydrophilized with methyl, ethyl and n-propyl alcohol at about 31% by weight and with n-butyl alcohol at about 40% (wt) and that the effect is absent at lower concentrations. It was shown that the results of polypropylene membrane hydrophilization were better if the alcohols with shorter alkyl chains were used, i.e. methyl, ethyl, and n-propyl alcohol. The use of a long-chain alcohol, e.g. n-butyl alcohol reduced the “effectness” of hydrophilization because the penetration of such an alcohol into the polypropylene membrane pores was hampered. *On leave from the Chemistry Department, University of Warsaw, ul. Pasteura 1, 02–093, Warsaw, Poland