Enhanced Mechanical Relaxation below the Glass Transition Temperature in Partially Supramolecular Networks

作者： Athanasios Dimopoulos , Jean-Luc Wietor , Michael Wübbenhorst , Simone Napolitano , Rolf A. T. M. van Benthem

关键词: Supramolecular chemistry 、 Chemical engineering 、 Physical chemistry 、 Stress relaxation 、 Creep 、 Glass transition 、 Polymer 、 Dynamic mechanical analysis 、 Relaxation (physics) 、 Chemistry 、 Differential scanning calorimetry

摘要: Cross-linked polymers in which part of the covalent cross-links have been replaced by reversible potential application coatings with improved stress relaxation. Here we present a detailed study materials based on copolymers e-caprolactone and l-lactic acid, containing different ratios ureidopyrimidinone (UPy) dimer cross-links. Their thermal mechanical properties were tested differential scanning calorimetry (DSC), dynamic analysis (DMA), dielectric relaxation spectroscopy (DRS). By extrapolation α* process DMA (arising from dynamics UPy cross-links) to temperatures below glass transition temperature (Tg), it was shown that contribute significantly Tg observed creep measurements.