Random copolymers based on terephthalate acid, succinic acid and ethylene glycol, with thermally induced shape memory,
were synthesized via melt polycondensation. The chemical structures of these poly(ethylene terephthalate-co-ethylene
succinate) copolymers (PET-co-ES) were ascertained by 1HNMRspectroscopy. The thermal and viscoelastic characteristics
of these copolymers were studied in terms of the succinic acid content using differential scanning calorimetry and dynamic
mechanical analysis. The shape memory effects of the copolymers were examined using the strain test. The experimental
results suggested that all copolymers exhibited shape memory above the glass transition temperature and that the highest
shape recovery rate was 90%. The shape recovery rates of all test samples declined with the number of cycles. This decrease
in the shape recovery ratemayresult fromthe change in the degree of polymer orientation and/or crystallinity during repeated testing.
