Influence of a Single Catenane on the Solid-State Properties of Mechanically Linked Polymers.

We report on mechanically linked polymers containing a single catenane in the middle of the chain. These polymers were synthesized by a simple procedure consisting in "clicking" polymer chains onto a functionalized palladium-templated [2]catenane, allowing the preparation of a variety of mechanically linked polymers. The flexibility of the catenane junction was modulated by removing the Pd ion from the catenane to unlock the macrocycles and increase their mobility. We show that this mobility change has a strong impact on the solid-state properties of the polymers. This is illustrated by studying the glass transition temperature of polystyrene-based polymers and the crystallization behavior of poly(ethylene oxide)-based polymers. Our study proves that a change of flexibility of a single catenane inserted into a polymer chain drastically influences the polymer behavior in the solid state.