Synthesis and properties of non-isocyanate aliphatic thermoplastic polyurethane elastomers with polycaprolactone soft segments

This study describes a non-isocyanate route for synthesis of aliphatic thermoplastic polyurethane elastomers (TPUEs) with excellent mechanical properties. Melt transurethane co-polycondensation of bis(hydroxyethyl) hexanediurethane with different polycaprolactone-diols was conducted at 170 degrees C under a reduced pressure of 3 mmHg to prepare a series of TPUEs. The TPUEs were characterized by gel permeation chromatography, FT-IR, H-1-NMR, wide angle X-ray scattering, DSC, TGA, dynamic mechanical analysis, atomic force microscopy, SEM, and tensile analyses. The TPUEs exhibited M-n above 18,100 g/mol, T-g of -35 to -11 degrees C, Tm of up to 107 degrees C, initial decomposition temperature over 269 degrees C, tensile strength up to 32 MPa with a strain at break of 1119%, and resilience of 65% to 83%. TPUEs with good tensile strength and resilience were successfully prepared through a non-isocyanate route.