COPOLYESTERAMIDES .6. HEXAMETHYLENE ADIPAMIDE HEXAMETHYLENE ADIPATE RANDOM AND ORDERED COPOLYMERS - MOLECULAR ASPECTS

Crystallinity in polyesteramides composed of the units NH(CH2)6NH·OC(CH2)4CO (A) and O(CH2)6O·OC(CH2)4CO (B) has been examined by X-ray diffraction and i.r. spectroscopy. Despite some discrepancy with results from thermal analysis, it is confirmed that copolymers containing ≥ 30 wt% of (A) units show only nylon 6,6 type crystallinity, whereas at high (B) contents dual (polyamide + polyester) crystallinity may occur but crystallization of the (B) component is impaired. i.r. Spectroscopy has also established the occurrence of amide-ester hydrogen bonding in (A)/(B) copolymers and in the related polymer [NH(CH2)6O·OC(CH2)4CO]n. The carbonyl group signals in the 13C-NMR spectra accord with the chain structures expected from the method of polymerization. © 1990.