Summary: A series of high molecular weight poly(butylene succinate) copolyester containing rigid imide units were synthesized in this paper. The chemical structure and composition of the copolyesters were determined by 1H NMR spectroscopy and Fourier transform infrared spectroscopy (FT‐IR). Gel permeation chromatography (GPC) was employed to determine the molecular weight and molecular weight distribution. The differential scanning calorimetry (DSC) technique showed that the melting temperature (Tm) of the copolyester decreased slightly with the increment in trimellitic imide unit content. When the imide unit content was increased to 6.3 mol‐%, it had an elongation at break of 510% (83% higher than that of PBS) and a tensile strength of 37 MPa (7% higher than that of PBS). The changes in mechanical properties of the copolyester might be owed to the compositive effects of spherulitic morphology and imide units.
