Structural investigations of segmented block copolymers. I. The morphology of poly(ether estermide)s based on poly(tetramethylene oxide) "soft" segments

• Published in: Journal of applied polymer science 1984-04, Vol.29 (4), p.1141-1155
• Main Authors: Perego, G., Cesari, M., Fortuna, G. Della
• Format: Article
• Language: English
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Properties and characterization; Structure, morphology and analysis
• ISSN: 0021-8995; 1097-4628
• DOI: 10.1002/app.1984.070290411

The morphology of poly(ether esteramide)s (PEEA) of the general formula [(6NT6)k‐PTMO]z has been investigated by wide and small angle X‐ray scattering and electron microscopy techniques. The copolymers are based on poly(esteramide) “hard” segments (containing an average number k of 6NT6 consecutive units) alternating poly(tetramethylene oxide) (PTMO) “soft” segments of constant length (MW ∼ 900). The fraction of crystallized 6NT6 increasing by increasing the PTMO content (i.e., by lowering k), approaching unity for k → 1. The morphology is of lamellar type, with both thickness and width of the crystalline domains (6NT6) decreasing with the increase of PTMO content; in the interlamellar amorphous regions both “soft” and “hard” segments tend to segregate in separate domains. For k ≃ 1, crystalline domains, formed essentially by isolated 6NT6 units, alternate with amorphous PTMO interlayers. The mechanism of evolution of the morphological structure as a function of the copolymer composition is discussed.