New injectable and self-healable thermoset polythiourethane based on S-aromatic thiourethane dissociative exchange mechanism

Abstract

Covalent adaptable networks (CANs) are polymer systems in which the crosslinks can undergo reversible rearrangement reactions. The stimuli-triggered dynamism of the network enables healing and reprocessing of pristine materials without damaging their original mechanical properties. In this paper, we show that thiourethane linkage is a promising dynamic covalent bond to create self-healable, injectable and recyclable polythiourethane (PTU) networks. Three different crosslinked PTU networks are thoroughly compared to understand the key features that influence the thermal reversibility of thiourethane moieties. FTIR and rheological measurements confirmed the underlying dissociative exchange mechanism. Finally, thermal recycling, self-healing and injectability of S-aromatic PTU are demonstrated.