Vitrimeric Silicone Elastomers Enabled by Dynamic Meldrum’s Acid-Derived Cross-Links

JacobS. A. Ishibashi, Julia A. Kalow

Index: 10.1021/acsmacrolett.8b00166

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Abstract

Current vitrimer technology uses only a handful of distinct reactions for cross-linking. New dynamic reactions can diversify vitrimer functionality and properties. In this paper, reversible cross-links formed by conjugate addition–elimination of thiols with a Meldrum’s acid derivative enable compression–remolding of silicone elastomers. After 10 remolding cycles, there is no discernible deterioration of mechanical properties (Young’s modulus, Tg, rubbery plateau E’), nor is there a change in stress relaxation activation energy. This robust new cross-linker could be implemented in any number of systems that currently use permanent thiol–ene cross-linking, expanding the scope of recyclable materials.