A novel biodegradable polyester from chain-extension of poly(p-dioxanone) with poly(butylene succinate)

Prepolymers of both poly(p-dioxanone) (PPDO) and poly(butylene succinate) (PBS) reacted in the presence of toluene-2,4-di-iso-cyanate(TDI) as a chain extender to produce higher-molecular-weight chain-extended products (PPDOBS) in suitable reaction conditions. The novel biodegradable polymers were characterized by NMR, DSC, TG and WAXD. The results of thermal oxidative degradation show that chain-extended products have better thermal stability than PPDO. The thermal degradation of PPDOBS shows two stages, the first due to the degradation of PPDO segment of PPDOBS, and the second to the degradation of PBS segment. DSC measurement shows that the PPDOBS has only one Tg, which means that PPDO has good compatibility with PBS. PPDOBS has two crystalline peaks during the cooling scan, but no crystalline peak during the heating scan. The diffraction peaks of PPDOBS appear at the same 2θ angles as that of homopolymers, suggesting that the PPDO and PBS of the chain-extended products preserve their own crystal form. This kind of novel biodegradable polymer is expected to have potential applications in environmentally friendly materials.