Poly(ethylene oxide) induced microstructure and hydrolytic degradation behavior changes of poly(butylene succinate)

Degradable polyesters exhibit wide application in many fields due to the fact that the waste of these polymers can be easily reclaimed, which greatly reduces the environmental risk. In this work, a small quantity of water-soluble poly(ethylene oxide) (PEO) was introduced into biodegradable poly(butylene succinate) (PBS). Crystallization behavior of the PBS matrix was comparatively investigated using polarized optical microscope (POM), differential scanning calorimetry (DSC) and wide angle X-ray diffraction (WAXD). The results demonstrate that PEO affects the crystallization behavior of the PBS matrix, which is greatly dependent upon the PEO content. At relatively low PEO content, accelerated crystallization is achieved for the PBS matrix, while the role of PEO becomes inconspicuous at relatively high PEO content. The sample surface hydrophilicity was evaluated through contact angle measurement of distilled water. The results demonstrate that incorporating PEO into PBS greatly enhances the hydrophilicity of the sample surface. The hydrolytic degradation measurements were carried out under an alkaline condition. The results clearly show that the presence of PEO accelerates the hydrolytic degradation of the PBS matrix. Furthermore, the sample obeys the surface erosion mechanism. The mechanism for the largely enhanced hydrolytic degradation ability is then analyzed.