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We report an advanced analysis protocol that allows to quantitatively study the course of step-growth reactions by size exclusion chromatography on the example of the depolymerization of a Diels-Alder polymer based on a furane/maleimide couple at elevated temperatures. Frequently occurring issues of molar mass calibrations and overlap of monomer with solvent signals are addressed for determining reliable molar masses. Thereby, even kinetic parameters (e.g., rate coefficients) can be derived that otherwise would require performing additional spectroscopic experiments. Our results confirm first-order behavior of the rDA reaction with an activation energy of 33 kJ mol -1 .

We report the transfer of entropic chain length effects into the realm of supramolecular chemistry and thereby demonstrate a macromolecular method to tune the reaction equilibria of hydrogen bonding motifs via the application of substituents of differing lengths and masses while not altering the actual recognition units to achieve a difference in the degree of association. The supramolecular adducts are characterized via temperature-dependent nuclear magnetic resonance (NMR) spectroscopy.