Comparative study of effect of low and medium dose rate of γ irradiation on microporous polysulfone membrane using spectroscopic and imaging techniques

The effect of low (LDR) and medium dose rate (MDR) of γ irradiation at low doses (0-100 kGy) on the structural and chemical changes of microporous polysulfone (PSf) membrane has been studied using UV-vis, FTIR, SEM and dead-end filtration techniques. PSf membrane was cast by phase inversion method. Irradiation was done at room temperature in air media. The doses chosen were 0-100 kGy for LDR and 0-50 kGy for MDR; they were below and above sterilization dose. Analysis of UV-vis and IR spectra and SEM images obtained suggested that chain scissions and crosslink had occurred simultaneously in the irradiated membranes in both cases. This radio-oxidation effects observed start at a very low dose i.e. 1.66 kGy and increase with increase in dose. It is supported by the flux values obtained; it is increased with increase in dose. The results indicate that a very low dose γ irradiation was able to change the physicochemical characteristics of microporous PSf membrane which depend on dose rate of exposure.