On-Demand Deconstructable Thermosets Through Cleavable Comonomer and Thermolatent Base Synergy.

Thermosets provide superior chemical and mechanical properties critical for high-performance applications, but their permanent crosslinked networks severely limit recyclability and end-of-life (EOL) management. Traditional approaches relying on cleavable comonomers enable degradation only through slow diffusion of acidic or basic solutions, hindering practical implementation. Here, on-demand deconstructable thermosets are developed by incorporating stimuli-responsive thermolatent bases alongside cleavable comonomers prior to polymerization. These latent species remain inert during thermal or photoinitiated curing, including vat photopolymerization 3D printing, preserving classical thermoset performance. Upon near-infrared photothermal or thermal activation (>100°C), rapid network deconstruction yields soluble branched oligomers, enabling efficient chemical recycling without aggressive solvents during service life. This strategy is demonstrated using thermolatent 1,5,7-triazabicyclo[4.4.0]dec-5-ene derivatives with radical copolymerization of dibenzo[c,e]oxepine-5-thione with styrene/acrylic monomers, as well as ring-opening metathesis polymerization of dicyclopentadiene with silyl ether-containing cyclic olefins. The approach offers programmable degradation for sustainable high-performance thermosets.