Taking advantage of β-hydroxy amine enhanced reactivity and functionality for the synthesis of dual covalent adaptable networks

Abstract

This study highlights the potential of β-hydroxy amines as building blocks for aza-Michael CANs.

Biobased catalyst-free covalent adaptable networks based on CF3-activated synergistic aza-Michael exchange and transesterification

“…Indeed, even if the comparison is not totally exact because of polymer matrix difference, relaxation times were up to 20 times lower at 130 °C for BAE-F compared to these non-fluorinated CANs. 41,42 This result is in good agreement with the preliminary molecular study that highlighted the strong activation of aza-Michael exchange induced by fluorine atoms.…”

“…Indeed, butanediol can be obtained from carbohydrates produced by hydrolysis of starch or bacteria fermentation, and epichlorohydrin can be synthesized from glycerol. 45,46 Moreover, β-hydroxyamines are known for their facile synthesis, and their high reactivity toward epoxides, 47 cyclic carbonates 48 and Michael acceptors 42 compared to conventional alkylamines due to the H-bonding assistance of the β-OH substituent. BD-β-HA was chosen for three main reasons: its chemical structure enabling the combination of aza-Michael addition and transesterification reaction with its β-OH substituent, its higher reactivity toward Michael acceptors and finally its eco-friendly synthesis.…”

“…38 We wish to present herein a material that associates this transesterification to a much less studied reaction, namely the aza-Michael exchange. 41,42 In this synergistic system, both reactions are activated by the same CF 3 group positioned on the -position to the ester. The effect of the CF 3 group was first highlighted on the aza-Michael addition and aza-Michael exchange reactions on model compounds.…”

Thia-Michael Reaction: The Route to Promising Covalent Adaptable Networks

“…The combination of aza-Michael exchange with transesterification was also evaluated in this initial article [ 89 ]. This work was then extended by our group in a study showing the enhanced reactivity of a β-hydroxyamine and its potential for the synthesis of dual covalent adaptable networks [ 90 ]. In these networks the presence of ester and hydroxyl functions allowed to perform transesterification as well as aza-Michael exchange.…”

Biobased, Creep-Resistant Covalent Adaptable Networks Based on β-Amino Ester Chemistry

“…Recently, β-amino esters were reported as a thermally dynamic motif for the design of CANs. − These β-amino esters are readily prepared by abundantly available building blocks using the aza-Michael reaction of an amine to an acrylate, making them a new promising motif to create dynamic polymer materials, with good thermal and hydrolytic stability . Despite the fact that the aza-Michael reaction was widely explored and studied previously, it was usually considered to create permanent bonds in bulk materials. , However, recently published studies showed that β-amino esters undergo both dynamic aza-Michael reaction andin the presence of free hydroxyl groupsa catalyst-free transesterification. − …”