POS1-0575
Crosslinker-Free Vitrimer Networks for Tunable Mechanics and Bond-Exchange-Assisted Blending
When and Where
Nov 30, -0001
12:00am - 12:00am
Presenter(s)
Youseop Lee (Korea University)
Co-Author(s)
Abstract
Vitrimers have emerged as sustainable next-generation thermosetting polymers due to their thermally induced reprocessability enabled by covalent adaptable networks. Herein, we present a versatile strategy for constructing crosslinker-free vitrimer networks based on catalyst-controlled thiol–epoxy and transesterification chemistry. A small-molecule model study was first conducted to screen suitable catalysts, as a single catalyst must promote both thiol–epoxy reaction and transesterification. Guided by the model study, vitrimer networks were synthesized and systematically characterized in terms of their thermal, rheological, and mechanical properties. This synthetic strategy was further applied to four different di-epoxy monomers, all of which successfully produced vitrimer networks with distinct mechanical properties depending on the backbone structure of the epoxy monomers. Furthermore, “homo” vitrimers prepared from different di-epoxy monomers were blended at elevated temperature, yielding homogeneous multi-component networks through bond exchange reactions. The blended vitrimers exhibited enhanced toughness due to the incorporation of flexible alkyl-based vitrimer segments. To demonstrate upcyclability, the resulting vitrimers were depolymerized into functional monomers, which were subsequently repolymerized to regenerate vitrimer networks. These results highlight a versatile crosslinker-free vitrimer platform that enables tunable mechanical properties and homogeneous network blending through dynamic bond exchange chemistry.
