Kim Namil, Huang Tsang-Min, Kyu Thein, Nosaka Mami, Kudo Hiroto, Nishikubo Tadatomi
Department of Polymer Engineering, University of Akron, Akron, Ohio 44325-0301, USA.
J Phys Chem B. 2008 Oct 23;112(42):13225-30. doi: 10.1021/jp803893k. Epub 2008 Sep 26.
The phase diagram of a mixture consisting of hyperbranched polyester (HBPEAc-COOH) and eutectic nematic liquid crystals (E7) has been established experimentally by means of differential scanning calorimetry and polarized optical microscopy subjected to prolonged annealing. The observed phase diagram is an upper azeotrope, exhibiting the coexistence of nematic + isotropic phase in the vicinity of 90 approximately 110 degrees C above the clearing temperature of neat E7 (60 degrees C). With decreasing temperature, a focal-conic fan shaped texture develops in the composition range of 63 approximately 93 wt % of the annealed E7/HBPEAc-COOH blends, suggestive of induced smectic phase in the mixture. Wide angle X-ray diffraction (WAXD) technique revealed the existence of higher order mesophase(s).
通过差示扫描量热法和长时间退火后的偏光显微镜，实验确定了由超支化聚酯（HBPEAc-COOH）和共晶向列型液晶（E7）组成的混合物的相图。观察到的相图是一个上共沸物，在纯E7的清亮点温度（60℃）以上约90至110℃附近呈现向列相+各向同性相共存。随着温度降低，在退火后的E7/HBPEAc-COOH共混物63至93 wt%的组成范围内形成了焦锥扇形织构，这表明混合物中诱导出了近晶相。广角X射线衍射（WAXD）技术揭示了高阶中间相的存在。
