FT-IR study of blends and complexes of poly(mono n-alkyl itaconates) with poly (N,N-dimethylacryl amide) and poly (ethyloxazoline)

This paper reports an FT-IR study of blends and complexes of poly(mono n-alkyl itaconates) with poly (N,N-dimethylacrylamide) (PDMA) and poly(ethyloxazoline) (PEOX). Strong hydrogen bonding has been found and both polybases have shown similar acceptor strengths. The extent of the interassociation has been estimated by spectral curve fitting of the polybase carbonyl band. The influences of the solvent medium and alkyl side group length of the poly (mono n-alkyl itaconate) on the interassociation extents have been discussed. Blend and complex interassociation behavior has been compared too. Results show that media influences the interassociation degree in systems with PDMA, but has negligible influence in systems with PEOX. Moreover, the interassociation degree in blends with PEOX does not depend on the length of the poly(monoalkyl itaconate) side group, while an interassociating ability loss is observed in blends with PDMA as the side group size of the polyacid increases. This different behavior is attributed to the greater interspacing between vicinal carbonyl groups in PEOX. Anyway, this band shows conformational sensitivity and reflects the conformational changes that are forced to adopt as the steric hindrances present in the medium (due to the bulky side groups of the polyacids) increase.