How solvent-free crosslinking conditions alter the chemistry and topology of hemiketal based polymer networks

T. Urbaniak; K.G. Hoffmann; M. Herrera-Glomm; H. Oschkinat; P. Schmieder; K. Koschek*

Polymer 229, 123986 (2021)

BA solvent free reaction of PCL based polyester polyols with a crosslinking molecule based on a vicinal tricarbonyl
results covalent adaptable polymer networks that differ in their thermal behavior, swelling, and solubility
properties. Mild processing results polymer networks based on hemiketal/ketone equilibrium with properties
typical for dissociative networks including dissolution in presence of water or elevated temperature and selfhealing
properties. Further thermal treatment of the polymer entails changes in swelling, and solubility properties.
Constant glass transition temperatures of the differently treated polymers indicate a steady overall
network density, but changes in the nature of the network structure. By varying the number of OH-groups, molar
mass and stoichiometric ratio of the polyester polyol and the crosslinking molecule, respectively, material
properties can be adjusted. This approach gives access to reversibly crosslinked polymers varying in their
responsivness and overall mechanical properties.