Synthesis and Characterization of Poly(ester-amide)s from Bis(2-oxazoline)s, Anhydrides, and Diols

Abstract

A new class of poly(ester-amide)s was prepared by reacting bis(2-oxazoline)s, carboxylic anhydrides, and diols of different structures. The polymerization proceeds through the formation of a dicarboxy ester by reaction of two anhydride molecules with one diol molecule and subsequent 2-oxazoline ring opening by attack of the dicarboxy ester. The whole process leads to linear poly(ester-amide)s, whose structures were established by carbon and proton NMR analysis. The thermal characteristics of the prepared polymers were studied by differential scanning calorimetry. Transition temperatures were found to increase with an increase in the polymer chain stiffness. Poly(ether-ester-amidels were also prepared by employing polyethylene glycol) as a comonomer, alone, or in a mixture with ethylene glycol, thus obtaining block segmented polymers.

Melt modification of poly(styrene-co-maleic anhydride) with alcohols in the presence of 1,3-oxazolines

“…Subsequently, the in situ generated carboxylic acid reacts with 1,3-oxazoline yielding poly(esteramide)s as shown in Figure 1 (pathway b). 23,24 Additionally, we have shown that in such a ternary system imide formation can occur as a minor side reaction, thus reducing molecular weight. 25 The aim of this study was to demonstrate that 1,3-oxazolines are suitable low molecular weight compounds able to promote solvent-free melt modification of SMA with alcohols and to achieve high anhydride conversion by reactive processing technology.…”

Synthesis and characterization of polyesteramides derived from an oxazoline-functional alcohol and dicarboxylic acid anhydrides

“…These observations confirm the result of Po et al that the equimolar reaction of an oxazoline, an anhydride, and an alcohol leads to esteramide formation without by-products. 7 In the case that zwitterion formation (see Fig. 1) occurs, the intermediate may be followed by the interception of this intermediate by the alcohol, thus preventing zwitterionic polymerization.…”

“…Po et al were the first to demonstrate that the bulk reaction of these three components leads to polyesteramides. 7 In this ternary system, the ␣,-dicarboxylic acids are generated in situ by conversion of two equivalents of cyclic anhydride with one equivalent diol. Subsequently, these in situ-formed ␣,-dicarboxylic acids can react with bis(oxazoline)s forming polyesteramides via chain extension.…”

Copolymerization of bis(2-oxazoline)s, anhydrides, and diols or diamines. Reaction mechanisms and polymer properties

“…compounds used as monomers in that study were diols having different structure, 2,2-(1,4-phenyl-Nuclear Magnetic Resonance ene)bis(2-oxazoline) (PBO) and 2,2-bis(2-oxa-1 H-NMR spectra were recorded using a Bruker zoline), and succinic (S) and phthalic (P) anhy-AM-300 spectrometer, on samples solutions in drides. 20 dimethylsulfoxide-d 6 at room temperature. The The aim of this article is to report on the prepachemical shifts are referred to TMS Å 0.0 ppm.…”