Physical effects of radiation processes in poly(aliphatic/aromatic-ester)s modified with e-beam radiation

In this paper, the physical effects of radiation processes in poly(aliphatic/aromatic-ester)s (PED) containing hard segments as in poly(butylene terephthalate)(PBT) and soft segments of dimer of linolic acid (DLA) are reported. PED materials were modified at various doses of ionising radiation (25, 50, 75 and 100 kGy). Radical processes initiated by radiation were investigated by the electron paramagnetic resonance (EPR) and gas chromatography (GC). The results revealed that radiation induced oxidation observed in two different multiblock PBT/DLA copolymers (containing 26 and 30 wt% hard segments, respectively) was strongly inhibited in the presence of α-tocopherol because a significant decrease in consumption of oxygen as well as in production of peroxyl radicals was confirmed.