尿素对聚己内酯二醇结晶性能的影响研究

Influence of urea on crystallization of polycaprolactone

通过添加小分子尿素制备了聚己内酯(PCL)/尿素复合物,以期改变PCL的结晶性能。利用显微熔点、X射线衍射(XRD)、差示扫描量热法(DSC)、偏光显微镜(POM)等手段研究了PCL/尿素复合物的熔程、结晶度、结晶形态以及结晶过程,通过傅里叶变换红外光谱仪分析了PCL/尿素复合物的结构。结果表明:PCL及其复合物的结晶形态均为球晶,复合物球晶的密集程度较纯PCL明显增加,随着尿素含量增加,球晶尺寸变小;PCL/尿素复合物的结晶度相比纯PCL略有降低;尿素的加入使PCL熔程变窄。这是由于尿素与PCL间产生了氢键,并起到了成核剂的作用。

PCL/urea complex was prepared by adding small molecular urea to improve the crystallinity of PCL. The melting range,crystallinity,crystal morphology and crystallization process of complex were studied by micro- melting point,X-ray diffraction (XRD),differential scanning calorimetry (DSC)and polarizing microscopy (POM).The structure of complexe was studied by fourier transform infrared spectroscopy (FT-IR).The results showed that the crystal morphology of PCL and its complex were spherulite,and the density of spherulite in complex was higher than pure PCL.The size of spherulite became smaller with the increase of urea content.The crystallinity of complex was slightly lower than pure PCL.The adding of urea narrowed the melting range of PCL.This was due to the hydrogen bonding between urea and PCL,and urea played a role in the nucleating agent.