Preparation of hyperbranched polymers by oxa-Michael addition polymerization

Abstract

Hyperbranched polymers with high molecular weights were synthesized by t-BuP2-catalyzed oxa-Michael addition polymerization of trifunctional hydroxyl and diacrylate monomers.

pH and thermo responsive aliphatic tertiary amine chromophore hyperbranched poly(amino ether ester)s from oxa‐Michael addition polymerization

“…Detail analysis of the 1 H NMR and 13 C NMR spectra found that the signals d′ were observed, indicating occurrence of the transesterification reaction during t ‐BuP 2 ‐catalyzed oxa‐Michael addition branching polymerization of TEOA and EGDA. The degree of transesterification (DT) and the degree of branching (DB) values were calculated from the 1 H NMR spectra (Figure 1b) according to our previous report method, [ 44 ] and the results were listed in Table 1. Despite presence of a relative high transesterification reaction, hyperbranched poly(amino ether ester)s with high branching degree were obtained (Table 1), because the transesterification reaction produce new hydroxyl groups, which could further react with acrylic double bonds through oxa‐Michael polymerization.…”

“…Despite presence of a relative high transesterification reaction, hyperbranched poly(amino ether ester)s with high branching degree were obtained (Table 1), because the transesterification reaction produce new hydroxyl groups, which could further react with acrylic double bonds through oxa‐Michael polymerization. [ 44 ]…”

“…[ 41–43 ] Recently, we developed an efficient approach to synthesize hyperbranched poly(ester‐ether)s via oxa‐Michael addition polymerization from commercially available trifunctional hydroxyl and diacrylate monomers using phosphazene base ( t ‐BuP 2 ) as a catalyst. [ 44 ] In this work, we report a straightforward method for the preparation of pH and thermo responsive hyperbranched poly(amino ether ester)s via t ‐BuP 2 catalyzed oxa‐Michael addition polymerization of triethanolamine (TEOA) with EGDA at room temperature (Scheme 1). The structure, fluorescence properties, pH, and thermo responsiveness and application of hyperbranched poly(amino ether ester)s were investigated in detail.…”

Step-growth polymerisation of alkyl acrylates via concomitant oxa-Michael and transesterification reactions

“…8 Moreover, diacrylates and diols have been employed to synthesize poly(ester-ether)s catalysed by phosphazene base. 9,10 In all mentioned reactions, inert conditions were necessary and oligomers with M n s up to 2000 Da were obtained. Moreover, concomitant transesterification was identified as a side reaction leading to the reconstruction of the repeat units.…”

“…Moreover, concomitant transesterification was identified as a side reaction leading to the reconstruction of the repeat units. [4][5][6][7][8][9][10] Further step-growth polymerisations of acrylates comprising two different reaction mechanisms are a combined condensation and oxa-Michael addition reaction of acrylic acid and diols catalysed by a Brønsted acid and a tail-to-tail dimerisation combined with a transesterification of hydroxy-functionalized methacrylates activated by a NHC catalyst. 8,11 Further, a combination of an oxa-Michael addition of HEA with a ringopening polymerisation catalysed by phosphazene base has been disclosed.…”