SEGMENTED POLYURETHANE ELASTOMERS WITH LIQUID-CRYSTALLINE HARD SEGMENTS .3. INFRARED SPECTROSCOPIC STUDY
SEGMENTED POLYURETHANE ELASTOMERS WITH LIQUID-CRYSTALLINE HARD SEGMENTS .3. INFRARED SPECTROSCOPIC STUDY
复制标题
DOI：
10.1021/ma00116a032
复制
发表时间：
1995-06
期刊：
影响因子：
5.5
通讯作者：
Weiming Tang;W. Macknight;S. Hsu
中科院分区：
文献类型：
--
作者：
Weiming Tang;W. Macknight;S. Hsu
用红外光谱法研究了嵌段液晶聚氨酯(LCPUE)。向列型液晶硬磁区起到物理交联键的作用，可以通过施加机械应变来定向。硬段可实现的取向作用是机械应变和应力软化共同作用的结果。此外，弹性变形导致中间相中一些硬段的重排，形成更有序的堆积。高温红外光谱与LCPUE的热转变相关联，在中间相各向同性上方存在液-液微相分离的形态。
Segmented liquid crystalline polyurethanes (LCPUE) have been studied by infrared spectroscopy. The nematic liquid crystalline hard domains act as physical cross-links and can be oriented by the application of mechanical strain. The orientation function achievable in the hard segments results from the combination of mechanical strain and stress-softening. Furthermore, elastic deformation induces the rearrangement of some hard segments in the mesophase into a more ordered packing. High-temperature infrared spectra have been correlated with thermal transitions of the LCPUE, and a liquidliquid microphase-separated morphology above the isotropization of the mesophase appears to exist.