POLYTRIMETHYLSYLYLPROPYNE GAS SEPARATION MEMBRANES MODIFIED BY RADIOCHEMICAL GRAFTING OF DIVINYLBENZENE

A radiochemical method was employed to obtain poly(1-trimethylsilyl-1- propyne) (PTMSP)-divinylbenzene (DVB) grafted films. DVB monomer vapor s were absorbed by the PTMSP, and the grafting reaction was thereafter accomplished by Co-60 gamma-irradiation in a nitrogen atmosphere. The films so obtained were tested for nitrogen-oxygen separation. The per formances of the membranes were studied as functions of time and perce nt of grafting. The DVB-grafted membranes show an increased selectivit y factor and stability with time. The experimental data and some SEM o bservations confirm the presence of large voids in the PTMSP matrix. T hese voids are responsible for permeability changes during operation a nd disappear after the grafting procedure.