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Abstract

Associating polymers are macromolecules with reversible, non-covalent interaction sites such as hydrogen bonds or ionic interactions. These dynamic associations enable properties like self-healing, stimuli-responsiveness, and enhanced mechanical and adhesive performance. A novel synthetic route for amine-containing associating polymers was developed, among which poly(aryl amine-containing cyclooctene) (P(ACC)), also referred to as aminated polyethylene (APE), stood out for its exceptional adhesion performance on low surface energy substrates like PTFE. This thesis focused on understanding the effects of simple amine–amine associations on polymer dynamics, their aging as well as the adhesion performance of APEs and its applications. The interplay between the reversible association and polymer chain dynamics in APE was mainly assessed through rheological characterization and the application of a modified tube-based reptation model for associating polymers. Complementary insights were provided by thermal analysis and analytical techniques such as FTIR and SAXS. Amine reversible associations were initially found to exert only a weak delay on the chain reptation process in freshly synthesized polymers. Over time, the polymers gradually transitioned from viscoelastic liquid to viscoelastic solid behavior, indicating an increasing influence of the amine associations. The transition could be viewed as a two-step process, first by an increasing number or strength of binary associations which lead to a stronger delay in the reptation process, followed secondly by the emergence of long lifetime sticker aggregations which resulted in a secondary plateau in the viscoelastic response. The adhesion performance of freshly synthesized APE was characterized with T-peel tests, and the effect of molecular weights and peel rates on peel strength were studied. The peel strength was found to strongly correlated with the samples’ linear and non-linear viscoelastic properties, as characterized by a Universal extensional fixture. A predictive peel strength model was thus developed, and failure criteria were successfully obtained by fitting the model to the experimental results. Finally, APEs were explored as adhesion promoters for commercial polymer bases to enable adhesion on low surface energy substrates. The resulting blend system demonstrated not only high peel strength but also enhanced stability and improved creep resistance compared to pure APE.