Synthesis and characterization of imide end‐capped oligoesters of terephthalic acid and 2‐methyl‐2‐propyl‐1,3‐propanediol

Hydroxytelequelic oligoesters of molecular weight ( M n ) between 500 and 3000 were prepared from dimethylterephthalate (DMT) and 2‐methyl‐2‐propyl‐1,3‐propanediol (MPPD) by ester interchange polycondensation. They were modified by reaction of their end hydroxyl groups with N ‐(4‐chlorocarbonylphenyl) maleimide and N ‐(4‐chlorocarbonylphenyl) nadimide. Spectroscopic (NMR), chromatographic (GPC), and calorimetric (DSC) analyses demonstrated that MPPD oligoterephthalates are less reactive than previously used glycols (diethylene glycol, DEG) and only nadimide‐modified oligomers could be readily synthesized. Attempts to introduce maleimide groups at the chain ends led to crosslinked materials. Furthermore, some relationships between molecular weight and properties ( T g , thermal stability, etc.) could be outlined. The oligomers, unmodified and modified, proved to be essentially amorphous.