Synthesis of cross-linked polyurethane with self-healing properties

Abstract

Prepolymer synthesized from toluene-2,4-diisocyanate (TDI) (hard segment), and polypropylene glycol (PPG-2000) (soft segment) was end-capped with difurfurylamine groups. A new cross-linked self-healing polyurethane was obtained via Diels-Alder reaction of the en-capped prepolymer with N,N’-bismaleimido-4,4’-diphenylmethane (BMI). Thermal reversibility of the Diels-Alder reaction (DA-reaction) between terminal furanic rings of the polyurethane prepolymer and bismaleimide cross-linking agent designed to be responsible for self-healing. Polymers were characterized by NMR and IR spectroscopy and thermal analysis (DSC and TGA). Thermal reversibility of the DA-bonds in the cross-linked polymer was confirmed by DSC. The synthesized polymer has good processability and potential recyclability.

Thermally Remendable Polyurethane Network Cross-Linked via Reversible Diels–Alder Reaction

“…Thermally remendable PUs containing difuran moieties were prepared by a two-step polymerization process and were characterized by FTIR and 1 H-NMR spectra (Scheme 2) using the same protocol we previously designed [31,44]. Briefly, Voranol 3138 reacted with 3 mol of TDI at 60 • C and then terminated with difurfurylamine resulted in transparent viscous liquid (PU-V0).…”