Dynamic covalent networks with tunable dynamicity by mixing acylsemicarbazides and thioacylsemicarbazides

Dynamic covalent networks (DCNs) use chemical bonds that break and reform at appropriate processing conditions to allow reconfiguration of the networks. Recently, acylsemicarbazide (ASC) motif has been added repertoire such dynamic bonds, which is capable hydrogen bonding as well bond exchange. In this study, we show its sulfur congener, thioacylsemicarbazide (TASC), also acts a bond, but exchanges slower rate than ASC moiety. addition, siloxane-based DCNs comprising either or TASC motifs varying composition both tunable relaxation dynamics, slow down with an increasing amount motifs. The reduction in stress goes hand creep network can be tuned by ASC/TASC ratio. All are readily processed using compression molding dissolve when treated excess hydrazide solution. ability control properties polymeric small changes molecular structure allows generalized synthetic approach while accommodating wide temperature window for application.