The relaxation behavior of poly(pheny1ene sulfide) (PPS) RytonTM film has been studied as a function of annealing temperatures, T,, ranging from 30°C to 140°C. Previously, this type of semicrystalline PPS film was shown to possess a very large fraction of constrained, or rigid, amorphous chains. Here we investigate relaxation of amorphous chains using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and thermally stimulated depolarization current (TSDC). DSC studies suggest that annealing causes the as-received PPS film to relax some of its rigid amorphous fraction and increase its crystallinity, for T, > Tr DMA results show a corresponding increase in the temperature location of the dissipation peak and a decrease in its amplitude when T, increases above 100°C. Analysis of the TSDC p-peak due to injected space charges trapped at the crystal/ amorphous interphase provides additional information about amorphous phase relaxation. This peak does not exist in amorphous film, or as-received film, or as-received films annealed a t lower T,. The p-peak does exist in cold-crystallized films and as-received films annealed a t higher T,. We suggest that crystallinity is a necessary, but not sufficient, condition for observation of a p-peak. In addition to crystallinity, the sufficient conditions for observation of a p-peak are existence of (1) a sharp and distinct crystal/amorphous interphase, to provide charge trapping, and, ( 2 ) a large fraction of liquid-like amorphous phase, to provide a pathway for charge transport. These conditions are not met in PPS semicrystalline films with very imperfect crystals and large amounts of rigid amorphous phase. In such films, the rigid amorphous phase has, like the crystal phase, a restricted molecular mobility that causes it also to restrict the mobility of space charge. The implications are that film PPS processed with a large amount of rigid amorphous phase chains will have superior barrier properties to the build-up of interfacial space charge.