Vitrimer is a new class of polymeric materials which can be reprocessed to any shape while being permanently cross-linked. We designed and synthesized a catalyst-free network with poly-(dimethylsiloxane)etherimide (PDMS-NH 2 ), terephthalaldehyde (TA), and tri(2-aminoethyl)amine (TREA) through the condensation reaction between amino groups and aldehyde groups. As a result of the exchange reaction of the dynamic imine bond obtained, this PDMS network exhibits the nature of vitrimer-like material, which is examined by solubility and stress-relaxation experiments, and the relaxation time is as short as 64 s at 130 °C. In addition, the vitrimer-like PDMS is malleable and capable of self-healing, and the mechanical properties can be maintained even after three consecutive breaking/mold pressing cycles. Especially, besides heating, this vitrimer-like PDMS can also be recycled and reshaped at ambient temperature due to the exchange reaction of dynamic imine bond when immersed in water, which will potentially lead to green processing of the elastomers.

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A homogenous silicone dielectric elastomer with simultaneously improved dielectric and mechanical properties is synthesized by designing a dual crosslinking network.

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It is a significant but challenging task to simultaneously reinforce and functionalize diene rubbers. Inspired by “sacrificial bonds”, the authors engineer sacrificial hydrogen bonds formed by pendent urazole groups in crosslinked solution‐polymerized styrene butadiene rubber (SSBR) via triazolinedione click chemistry. This post‐crosslinking modification reveals the effects of the sacrificial bonds based on a consistent covalent network. The “cage effect” of the pre‐crosslinked network facilitates the heterogeneous distribution of urazole groups, leading to the formation of hydrogen‐bonded multiplets. These multiplets further aggregate into clusters with vicinal trapped polymer segments that form microphase separation from the SSBR matrix with a low content of urazole groups. The clusters based on hydrogen bonds, serving as sacrificial bonds, promote energy dissipation, significantly improving the mechanical properties of the modified SSBR, and enable an additional wide transition temperature region above room temperature, which endows the modified SSBR with promising triple‐shape memory behavior.