A process for preparing a poly(arylene sulfide) and copolymer thereof from a poly(arylene sulfide disulfide) is provided which comprises contacting the poly(arylene sulfide disulfide) with a polyhalo-substituted cyclic compound having unsaturation between adjacent ring carbon atoms and having halogen atoms attached to the ring carbon atoms in a polar organic compound and a basic compound at an elevated temperature. Alternatively, the poly(arylene sulfide disulfide) can be substantially dissolved in the polar organic solvent at elevated temperature to form fragments which can be contacted with the polyhalo-substituted cyclic compound in a polar organic compound and a basic compound at an elevated temperature. The fragments also can be isolated, recovered and then contacted with the polyhalo-substituted cyclic compound in a polar organic compound and a basic compound at an elevated temperature.