Copolymers and Terpolymers of Tetramethylene Urea, γ-Butyrolactone, and Ethylene Carbonate or 1,2-Propylene Carbonate

Tetramethylene urea (TeU) is successfully copolymerized with γ-butyrolactone (γBL), leading to an alternating poly(amide urethane) with alternating carbonyl-amino-tetramethylene-amino and carbonyl-trimethylene-oxy repeating units ( M̄ n = 12 600; M̄ w = 21 100; M̄ n = 1.67) and with a T m of 196.5 °C and a T g of 36.4 °C. Small defects in the microstructure of the alternating poly(amide urethane) arise from the formation of TeU−TeU diads. Furthermore, TeU is successfully copolymerized with mixtures of γBL and ethylene carbonate (EC) or 1,2-propylene carbonate (PC). From NMR spectroscopic data of the terpolymers obtained, it is concluded that the reactivity of the five-membered cycles used increases in the following order: EC ≫ PC ≈ γBL. It is possible to increase the content of γBL repeating units in the poly[(TeU−γBL)- stat -(TeU−EC)] or poly[(TeU−γBL)- stat -(TeU−PC)] by increasing the fraction of γBL in the feed. 13 C NMR spectroscopy reveals that TeU−EC or TeU−PC and TeU−γBL units are randomly distributed in the polymer chain. This conclusion is supported by the thermal properties.