133651-68-0Relevant articles and documents
Double Reversible Networks: Improvement of Self-Healing in Hybrid Materials via Combination of Diels-Alder Cross-Linking and Hydrogen Bonds
Sch?fer, Sandra,Kickelbick, Guido
, p. 6099 - 6110 (2018/08/21)
Intrinsic self-healing materials rely on a reversible bond formation after failure. In this study we report hybrid materials that contain two intrinsic self-healing forces: The reversible covalent bond formation of Diels-Alder groups is supported by intrinsic hydrogen bonds, which form supramolecular interactions and contribute to the mobility and proximity of the DA groups. This concept was realized by a combination of urea group containing spherosilicates with butyl methacrylate based polymers bearing both DA moieties and self-assembling hydrogen bonds. Multifunctional one-component polymers were synthesized and studied regarding their application in self-healing hybrid materials. The self-healing behavior was investigated following the signals for bond release and formation of DA groups in the material using IR, UV-vis, and CP-MAS NMR spectroscopy. Furthermore, DSC and rheological measurements were performed and revealed that the materials are superior compared to previously studied systems concerning their healing capacity. The self-healing behavior of the formed hybrid materials was proven by a cut healing test of several millimeters using microscope images. We can conclude that it is advantageous to combine several reversible functions in one material to promote the self-healing capacity particularly in nanocomposites where the flexibility of the network is restricted.
