fifth reprocessing cycle the impact strength of the polycarbonate was below the detection limit of the equipment (Table 2). These results showed that PC undergoes degradation during reprocess- ing. This decrease of impact strength as the material is reprocessed is in agreement with the observed by other authors. Eguiazabal and Nazabal (1989) observed a continuous decrease in the impact properties of PC with the number of processing cycles, in clear agreement with the observations by Abbas (1980) using a Charpy impact test. An even faster loss of impact strength was observed from the third cycle onwards. Shea et al. (1977) investigated the recycling of polycarbonate in the injection molding of connector caps, and observed a significant increase in melt flow, which could be correlated to decreases in impact strength and molecular weight. Although break stress, elongation at break and impact resistance decreased as a result of successive cycles, no influence of repro- cessing was apparent in the modulus of elasticity or in the yield stress.