高等学校化学学报 ›› 2004, Vol. 25 ›› Issue (5): 988.

• 研究简报 • 上一篇    

端基含36个4-硝基偶氮苯介晶基元的二代树状碳硅烷的液晶性研究

张其震1, 盛昕1, 殷晓颖1, 李光2, 季怡萍2   

  1. 1. 山东大学化学化工学院, 济南 250100;
    2. 中国科学院长春应用化学研究所, 长春 130022
  • 收稿日期:2003-01-27 出版日期:2004-05-24 发布日期:2004-05-24
  • 通讯作者: 张其震(1937年出生),男,教授,主要从事液晶高分子研究.E-mail:qzzhang@sdu.edu.cn E-mail:qzzhang@sdu.edu.cn
  • 基金资助:

    国家自然科学基金(批准号:29874020,59573029);山东省自然科学基金(批准号:Y95B0720);中国科学院长春应用化学研究所高分子物理重点实验室基金资助

Studies on Liquid Crystalline of Carbosilane Dendrimer of the Second Generation Containing Thirty-six 4-Nitroazobenzene Mesogenic Groups in Its Periphery

ZHANG Qi-Zhen1, SHENG Xin1, YIN Xiao-Ying1, LI Guang2, JI Yi-Ping2   

  1. 1. School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China;
    2. Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
  • Received:2003-01-27 Online:2004-05-24 Published:2004-05-24

关键词: 树状化合物, SE相和SA相液晶, 硝基偶氮苯, 碳硅烷

Abstract: Liquid crystalline of a new carbosilane dendrimer of the second generation(D2) containing thirty-six 4-nitroazobenzene groups in its periphery was characterized by means of polarizing optical micrograph, DSC and WAXD. Mesogenic compound M5 exhibits threaded, schlieren and inversion lines texture of the nematic phase on the cooling from isotropic phase to solidified temperature. Dendrimer D2 shows the focal conic fan-shaped texture of the smectic A phase on the heating course from 69 to 187 ℃ and on the cooling course from 183 to 64 ℃. After cooling, the smectic E(SE) phase with a texture of the focal conic fan-shape with stripes and concentric arcs appears from smectic A(SA) phase. Phase behavior of dendrimer D2 in liquid crystalline state was K69SA187I182SA57SE47K. The isotropic-smectic A transition enthalpy, smectic A-smectic E transition enthalpy and isotropic-smectic A transition entropy were 1.8, 4.5 and 4.0 J/(K·mol), respectively, and were in agreement with or close to those of small molecular liquid crystal.

Key words: Dendrimer, Smectic E and A liquid crystal, Nitroazobenzene, Carbosilane

中图分类号: 

TrendMD: