Improvement of thermal stability, crystallinity and degradation of poly(butylene carbonate) by incorporation of bio-based poly(ethylene sebacate) segment

Multiblock poly(carbonate-co-esters) (PBC-PESe) containing poly(butylene carbonates) (PBC) and bio-based poly(ethylene sebacate) (PESe) had been synthesized successfully by chain-extension of dihydroxyl terminated PBC (PBC-OH) and PESe (PESe-OH) using 1,6-hexmethylene diisocyanate as chain extender. The chemical structures, molecular weights, crystallization behaviors, and thermal and degradation properties of the copolymers were all characterized by proton nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, gel permeation chromatography, differential scanning calorimetry, polarized optical microscope, thermogravimetry analysis, water contact angle, and hydrolytic degradation. The resulting copolymers PBC-PESe all had a sole glass transition temperature (Tg), indicating the two segments, PBC and PESe, were well compatible in the amorphous phase. PESe segment acted a significant role on enhancing the thermal degradation temperature and hydrolytic degradation rate of multiblock copolymers. And the crystallization rate of PBC got dramatically accelerated after PESe segment was incorporated. However, the crystallization mechanism did not change. Furthermore, the mechanical properties of multiblock copolymers could be adjusted by changing the feed composition. Copyright © 2017 John Wiley & Sons, Ltd.