含二苯乙炔液晶基之側鏈液晶高分子的介電及二次非線性光學性質研究

Dielectric Relaxation and Second-order Nonlinearity of Side- chain Liquid Crystalline Polymethacrylates Containing Tolane- based Mesogenic Group

許哲愷(Zhe-Kai Xu)

指導教授 ： 黃振球 ； 薛敬和

元智大學/工程學院/化學工程與材料科學學系/碩士(1996年)

摘要

A series of Side-chain Liquid Crystalline Polymethacrylates with
different tolane-based mesogenic group content have been
synthesized. The mesogenic group content was characterized with
1H-NMR for the polymers. The phase behaviors were determined by
the differential scanning calorimeter, and optical polarizing
microscopy. A smectic A phase was obtained when the mesogenic
group content was increased up to 80 mol. %. Dielectric
relaxation behaviors were studied by a broadband dielectric
spectroscopy. The a-relaxation (associated with the glass
transition) behaviors were described by the Williams-Landel-
Ferry, and Havriliak-Negami equations, and discussed in terms of
structure and temperature dependencies. To study the
effect of liquid crystal (LC) phase on the nonlinear optical
(NLO) properties, the second-order nonlinearity of the poled
SCLCPs was measured. Relaxation behavior of the NLO properties
was achieved by the in-situ second-harmonic generation (SHG)
technique, and subsequently by curve-fitting with Kohlrausch-
Williams-Watts equation. The relationship among the chemical
structure, thermal dynamic behavior, and second-order nonlinear
optical properties were studied for the polymers.

關鍵字

二次非線性光學 ； 介電緩和 ； 二次諧波 ； 側鏈液晶高分子 ； 化學工程 ； 化學

並列摘要

無資料

並列關鍵字

Second-order Nonlinear Optical ； Dielectric Relaxation ； Second harmonic generation ； Side-chain liquid crystalline polymer ； CHEMICAL-ENGINEERING ； CHEMISTRY