A STUDY OF THE PERMEABILITY PROPERTIES OF SURFACTANT MODIFIED POLY(VINYL CHLORIDE) MEMBRANES

Poly(vinyl chloride) (PVC) membranes modified with the surfactants Twe en 80, Triton X-100 and bis(2-ethylhexyl) hydrogenphosphate (BEP) have been developed which mimic the high permeability and selectivity prop erties of conventional dialysis membranes to a range of low molecular weight solutes. Surfactant loss from the membrane matrix (through phys ical leaching) was minimised when plasticising with BEP. a species whi ch possessed extensive side-chain branching. The permeability of PVC p lasticised with BEP, however, was uniquely shown to vary with the natu re of the buffer and pH. A rationale is provided for these observation s.