In this work, vitrimeric elastomers based on functionalized poly(dimethylsiloxane) are realized. By exploiting reactions of epoxide functional groups with carboxylic acids in the presence of a covalently bonded amine catalyst, dynamic networks are formed to establish their potential in reversible adhesives. The dynamic nature of the networks is characterized thermo‐mechanically, and in tensile tests 85% of the stress at break can be recovered after reprocessing. The covalent adaptable networks are further subjected to damp heat tests, temperature cycling tests, and high temperature storage with the aim to establish the potential and boundaries of the dynamic character of the network after application in harsh environments. The influence of the ageing tests on the reprocessability and mechanical properties is evaluated via infrared spectroscopy and lap‐shear tests. While the damp heat tests (85 °C, 85% relative humidity, and 2000 h duration) lead to hydrolytic bond cleavage of the ester bonds and storage at 120 °C for 930 h oxidizes the hydroxy groups, temperature cycling tests (−40 to 85 °C, 50 cycles) does not degrade the mechanical properties and the dynamic nature of the networks and rejoined lap‐shear specimen exhibit a remaining bond strength of more than 70%.

Poly(ionic liquids) (PILs) and ionenes are polymers containing ionic groups in their repeating units. The unique properties of these polymers render them as interesting candidates for a variety of applications, such as gas separation membranes and polyelectrolytes. Due to the vast number of possible structures, numerous synthesis protocols to produce monomers with different functional groups for task-specific PILs are reported in literature. A difunctional epoxy-IL resin was synthesized and cured with multifunctional amine and anhydride hardeners and the thermal and thermomechanical properties of the networks were assessed via differential scanning calorimetry and dynamic mechanical analysis. By the selection of suitable hardeners, the glass transition onset temperature (Tg,onset) of the resulting networks was varied between 18 °C and 99 °C. Copolymerization of epoxy-IL with diglycidyl ether of bisphenol A (DGEBA) led to a further increase of the Tg,onset. The results demonstrate the potential of epoxy chemistry for tailorable PIL networks, where the hardener takes the place of the ligands without requiring an additional synthesis step and can be chosen from a broad range of commercially available compounds.

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