Self-Healing Polymer Networks Based on Reversible Michael Addition Reactions

A new polymeric material utilizing a highly efficient as well as reversible thiol-ene click reaction is presented. For this purpose, a trithiol is reacted with a bisbenzylcyanoacetamide derivative resulting in the formation of a dynamic polymer network. The self-healing ability of this novel material is tested by scratch healing experiments. Healing is found to take place from 60 degrees C onward. The underlying healing mechanism is studied in detail using temperature-dependent Raman spectroscopy confirming the reversible opening of the thiol-ene adducts. Additionally, the thermal and mechanical properties are investigated by differential scanning calorimetry, thermogravimetric analysis, and rheological measurements proving the network formation as well as its reversibility during the thermal treatment.