This communication describes a convenient route to optically active propylene carbonate by a catalytic kinetic resolution process resulting from the coupling reaction of CO2 and racemic epoxides using simple chiral SalenCo(III)/quaternary ammonium halide catalyst systems.
Vitrimers
endow cross-linked polymers with malleability and reprocessability
via exchange reactions. However, designing of reprocessable, shape-memory
polymer materials with high strength via a catalyst-free method remains
a challenge under mild conditions. Here, we propose a facile strategy
to address this dilemma by introducing the exchangeable imine bond
and N-coordinated boroxine into a polybutadiene (PB)-based network.
Specifically, PB grafted with 2-aminoethanethiol is reacted with the
formyl group of phenylboronic acid and dehydrated to form a dual-dynamic
covalently cross-linked network at room temperature. The dynamic network
draws on the advantage of imine (toughness) and N-coordinated boroxine
(strength), making the PB-based materials exhibit favorable malleability,
mechanical property, reprocessability, and thermal-induced shape-memory
behavior. We can obtain customized high mechanical properties by tuning
the cross-linking density, and the tensile strength reaches a high
value (12.35 MPa) without fillers or any other additives. Meanwhile,
the unique network framework makes the material recycle over several
times without sacrificing its property. This work presents a facile
and effective approach to achieve a multifunctional polymer with customized
attributes. Besides, this strategy can recycle end-of-life rubber
to alleviate environmental pollution and provide inspiration for fabricating
targeted materials by uniting the dynamic covalent or noncovalent
bonds.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.