Reprocessable, high-performance, and degradable bio-based polyhydroxyurethane vitrimers from a Musk T diamide dicyclocarbonate and a vanillin-glycerol epoxy adduct

Research on biobased polyhydroxyurethane (PHU) vitrimers has attracted increasing attention due to their sustainable development. In this paper, new biobased amide-containing PHU vitrimers (PHUAs) with imine (IM) dynamic covalent bonds mainly were prepared from an ethylene brassylate (Musk T) diamide dicyclocarbonate, a vanillin – glycerol epoxy adduct as the crosslinker, and 1,12-dodecanediamine. The diamide and aromatic vanillin segments imparted excellent mechanical properties to PHUAs. IM bonds provide prominent reprocessability at low reprocessing temperature (120 °C) and good degradability in 2 M HCl–THF (v:v,1:4) mixture solution. PHUAs exhibit excellent mechanical properties with the maximum tensile strength of 60.1 MPa and excellent twice reprocessing efficiency of 87.7 – 97.8%. Although PHUAs contain IM and hydroxyurethane dual dynamic covalent bonds, the IM bonds play the major role in dynamic exchange due to low stress relaxation temperatures (50–70 °C) and low E a (52.73–80.34 kJ/mol) of PHUAs. This study establishes a promising strategy to synthesize strong degradable PHU vitrimers with prominent reprocessing and degradability from renewable substances.