Liquid crystalline side-group block copolymers with triblock structure: Investigations on the influence of the block arrangement on the morphology and the LC-phase behavior
✍ Scribed by S. Poser; H. Fischer; M. Arnold
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 639 KB
- Volume
- 34
- Category
- Article
- ISSN
- 0887-624X
No coin nor oath required. For personal study only.
✦ Synopsis
Liquid crystalline triblock copolymers with LC inner block and amorphous outer blocks have been synthesized by "living" anionic polymerization and investigated using DSC, TEM, and small-angle x-ray diffraction. All samples of poly[styrene-block-2-(3-cholesteryloxycarbonyloxy) ethyl methacrylate-block-styrene] (PS-b-PChEMA-b-PS) show liquid crystalline behavior and phase separation between the blocks. Compared to triblock copolymers with PS inner block (PChEMA-b-PS-b-PChEMA) and diblock copolymers (PSb-PChEMA) the LC block copolymers with PS outer blocks have the same properties. The LC behavior and the morphology do not depend on the block arrangement; they are only influenced by the volume fractions of the blocks. Those samples in which the liquid crystalline subphase is not continuous (spheres) only a nematic phase was found, whereas in all samples with a continuous liquid crystalline subphase, the smectic A phase of the homopolymer was observed.