Dielectric Properties of Dual-Frequency Reactive Mesogens before and after Photopolymerization

Materials

Takayuki Kumagai¹  Hiroyuki Yoshida¹ 

[1] Division of Electrical, Electronic and Information Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan; E-Mails:

关键词: reactive mesogen;    dielectric property;    dual frequency;    liquid crystal;    photopolymerization;    dielectric anisotropy;   

DOI  :  10.3390/ma7021113

来源: mdpi

【 摘 要 】

The dielectric properties of reactive mesogens before and after photopolymerization were investigated. Commercially available nematic reactive mesogens (RMS03-013C, Merck) were measured and found to be dual-frequency liquid crystals. The property arose from the δ-relaxation process that was caused by rotational fluctuations parallel to the molecule’s long axis. After polymerization, the polymerized reactive mesogens still exhibited this dual-frequency property. The result was attributed to the β-relaxation process which arose from rotational fluctuations of localized parts of the main chain. The sign change of the dielectric anisotropy with increasing frequency after polymerization was opposite to the sign change before polymerization.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland