SYNTHESIS AND CHARACTERIZATION OF ALIPHATIC POLY(ESTER-AMIDE)S CONTAINING SYMMETRICAL BISAMIDE BLOCKS

A series of symmetrical diols were synthesised through ring-opening of lactones with different ring sizes by alkane diamines in moderate to good yields. Ring-opening of the dilactones glycolide and lactide with a diamine in equimolar amounts afforded symmetrical diols in quantita tive yield. Aliphatic poly(ester-amide)s were prepared by polycondensa tion of N,N'-bis(caproyl)butane diamide, dimethyl adipate and 1,4-buta nediol. The structure of the diamide was retained in the polymer. The polymers synthesized are semi-crystalline materials that possess order ed structures in the solid phase over almost the entire copolymer rang e. Depending on thermal history and copolymer composition thermal anal yses is in agreement with the presence of pseudo-hexagonal crystal str uctures below 75 degrees C, a fast melting recrystallization at this t emperature and a triclinic structure at higher temperatures.