【摘要】 用小角X射线散射（SAXS）方法研究聚氨酯这种多嵌段共聚物的微相分离现象及其微区结构的变化，指出微相分离程度DPS的变化与软段平均尺寸ls相关。这是由于ls的增大，大分子柔性增加，有利于大分子运动，有助于软硬段的不相容性而各自聚集成相畴的趋势。同时讨论了Porod非均匀长度lp与硬段体积分数φH、DPS及硬段平均尺寸lH之间的变化关系。更多还原

【Abstract】 The microphasc separation and the structure were studied by Small-Angle X-ray Scattering method. The results indicate that the degree of microphasc separation (DPS) is proportional tothe average length of soft-segment ls. Reasons for the occurrence are that the separation bocomeseasier in case ls and the flexibility of molecule chains increase. The relationships between the Porod’s non-uniform length lp and the volume fraction of hard-segments φH, DPS, and theaverage length of hard-segments lH were also discussed meanwhile.更多还原