“Solid-Liquid” Vitrimers Based on Dynamic Boronic Ester Networks

The “solid-liquid” behavior of vitrimers have not been systematically investigated. Herein, a series of “solid-liquid” vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized via thiol-ene click reactions. These vitrimers allow for flexibile modulation of their network structures and thus show a range of intriguing properties including high stretchability, flexible transition from elasticity to plasticity, strong strain rate dependence, and solid-liquid performance. The dynamic association rate of boronic ester bonds within these vitrimers could be apparently accelerated via increasing the content of boronic ester, which could be used to shape-program the flat vitrimer films into various complex 3D structures just with external force. Materials with such versatile dynamic behavior may open up a range of new applications.