Molecular Exchange of Dynamic Imine Bond for the Etching of Polymer Particles

Abstract

The underlying trend of colloidal synthesis has focused on extending the structure and composition complexity of colloidal particles. Hollow and yolk-shell particles are successful examples that have potential applications in frontier fields. In this paper, a facile and controllable etching method based on the molecular exchange of the dynamic imine bond to generate cavities in polymer particles is developed. Starting from boronate ester polymer particles and inorganic@boronate core-shell particles with the imine bonds incorporated in the polymer networks, the etching method easily affords hollow and yolk-shell particles with tunable shell thicknesses. The molecular exchange dynamics analysis indicates that guest amine molecules cause the reconstruction of imine bonds and the leakage of molecular and oligomer fragments, resulting in the formation of the hollow structure. This molecular exchange-based etching method may be of interest in the construction of polymer architectures with increased composition and structure complexities.

Recoverable Rosin-Based Epoxy Vitrimers with Robust Mechanical Properties and High Thermostability

“…Moreover, the reversible hydrolysis property of β-hydroxy ester bonds makes it possible to achieve the reversible conversion of the de-cross-linked network and cross-linked, which is able to impart the degradable capability and chemical recycling . Furthermore, it is reported plentiful epoxy vitrimer systems involved in various dynamic covalent bonds, for instance disulfide, , boronic ester, , siloxane, , imine, , etc. Among them, boronic ester bonds show three types of exchange mechanisms, namely: transesterification, dioxaborolane metathesis, and boroxine metathesis.…”

“…Moreover, the reversible hydrolysis property of β-hydroxy ester bonds makes it possible to achieve the reversible conversion of the de-cross-linked network and cross-linked, which is able to impart the degradable capability and chemical recycling. 8 Furthermore, it is reported plentiful epoxy vitrimer systems involved in various dynamic covalent bonds, for instance disulfide, 9,10 boronic ester, 11,12 siloxane, 13,14 imine, 15,16 another one in the condition of catalyst-free and solvent-free, maintaining the network integrality and it can take place potentially at wide range of temperature, providing a facile approach for preparation epoxy vitrimers. 17 Currently, few of the epoxy vitrimers based on DTER show rapid stress−relaxation for deformation at moderate conditions; therefore, the second dynamic covalent bonds are introduced to epoxy vitrimers based on DTER to accelerate the rate of exchange reaction.…”