AbstractThe radiation resistance of a series of aromatic polysulfones comprising alternating units of diphenyl sulfone and various aromatic diols has been investigated by measuring volatile products, soluble fractions and electron spin resonance (ESR) spectra. The yields of radicals at 77 K observed by ESR and of SO2at 423 K have indicated that biphenol gives enhanced resistance to Y radiation, and tetramethyl bisphenol‐A decreased resistance, relative to bisphenol‐A, bisphenol‐S and hydroquinone. The protective effect of bisphenol was confirmed by lower scission and crosslinking yields determined from the soluble fractions after high