Polymer Engineering and Science, Vol.61, No.2, 497-505, 2021
Synthesis and properties of self-healing cross-linked nonisocyanate polyurethanes from biobased diglycerol bis(cyclic carbonate)
A simple and green method was established to prepare self-healing cross-linked nonisocyanate polyurethanes (SH-cNIPUs) from biobased diglycerol bis(cyclic carbonate) (DGDC). Two nonisocyanate polyurethane prepolymers with furan terminal groups (tFU-NIPUs) were synthesized through a ring-opening reaction of DGDC with furan methylamine and trimethylolpropane tris(poly[propylene glycol], amine terminated) ether, or tris(2-aminoethyl) amine under mild conditions. The SH-cNIPUs were prepared via a Diels-Alder reaction between tFU-NIPUs and a bismaleimide. SH-cNIPUs were characterized by ATI-FTIR, H-1 NMR, differential scanning calorimetry, polarized optical microscope, and tensile strength after being damaged and healed. SH-cNIPUs with glass transition temperature from 8 to 49 degrees C, tensile strength up to 21 MPa, and self-healing efficiency from 67 to 80% were successfully synthesized.