摘要
ＳｔｕｄｉｅｓｏｎｍｉｃｒｏｄｏｍａｉｎｓｔｒｕｃｔｕｒｅｉｎｓｅｇｍｅｎｔｅｄｐｏｌｙｅｔｈｅｒｐｏｌｙｕｒｅｔｈａｎｅｕｒｅａｓｂｙｐｏｓｉｔｒｏｎａｎｎｉｈｉｌａｔｉｏｎｌｉｆｅｔｉｍｅａｎｄｓｍａｌａｎｇｌｅＸｒａｙｓｃａｔｅｒｉｎｇ?..
The microdomain structure of segmented polyether polyurethaneureas is investigated by means of positron annihilation lifetime spectroscopy, small angle X ray scattering and differential scanning calorimetry. The experimental results show that the decrease in the domain volume and free volume results from the increase in the hard segment (polyurethaneurea segment) contents as the number average molecular weight M n of the soft segments (polyethylene glycol segments)is the same, and that the increase in domain volume and free volume result from the increase in the M n of the soft segments when the hard segment content is the same or nearly the same. These results demonstrate that positron annihilation lifetime spectroscopy is a sensitive technique to probe the microdomain structure in polymers.
关键词
聚醚聚氨酯-脲
微观区结构
X射线散射
Positron annihilation, Small angle X ray scattering,Segmented polyether polyure thaneurea, Domain structure, Glass transition temperature
