Synthesis and characterization of new optically active poly(amide-imide-urethane) thermoplastic elastomers, derived from 4,4 '-(hexafluoroisopropylidene)-N,N '-bis(phthaloyl-L-leucine-p-aminobenzoic acid) and PEG-MDI

摘要

A new class of optically active poly(amide-imide-urethane) was synthesized via two-step reactions. In the first step, 4,4'-methylene-bis(4-phenylisocyanate) (MDI) reacts with several poly(ethylene glycols) (PEGs) such as PEG-400, PEG-600, PEG-2000, PEG-4000, and PEG-6000 to produce the soft segment parts. On the other hand, 4,4'-(hexafluoroisopropylidene)-N,N'-bis(phthaloyl-L-leucine-p-amidobenzoi c acid) (2) was prepared from the reaction of 4,4'-(hexafluoroisopropylidene)-N,N'-bis(phthaloyl-L-leucine) diacid chloride with p-ammobenzoic acid to produce hard segment part. The chain extension of the above soft segment with the amide-imide 2 is the second step to give a homologue series of poly(amide-imide-urethanes). The resulting polymers with moderate inherent viscosity of 0.29-1.38 dL/g are optically active and thermally stable. All of the above polymers were fully characterized by IR spectroscopy, elemental analyses, and specific rotation. Some structural characterization and physical properties of this new optically active poly(amide-imide-urethanes) are reported. (C) 2003 Wiley Periodicals, Inc. [References: 14]