Synthesis and Characterization of Photopolymerizable Liquid Crystalline Compounds Having Two Reactive Sites

Bulletin of the Korean chemical society

Ji Young Chang¹  Suk Hoon Kang¹  Ki Suk Jang¹ 

关键词: Polymerizable liquid crystal;    Diacetylene;    UV irradiation;    Photopolymerization;   

DOI  :  

学科分类：化学（综合）

来源: Korean Chemical Society

【 摘 要 】

Rod-like polymerizable LC molecules having two different reactive groups, i.e. acryl and diacetylene groups were prepared. 4-Hydroxyphenyldiacetylenes were synthesized by the coupling reaction of 1-bromoalkynes with 4-ethynylphenol and then reacted with 4-(6-acryloyloxyalkyloxy)benzoic acid to give polymerizable LC molecules 4a-d. The mesomorphic properties of compounds 4a-d were investigated by differential scanning calorimetry, polarized optical microscopy and X-ray diffractometry. Compounds 4a-c exhibited smectic and nematic phases, but compound 4d having a longest alkyl tail among the series formed only a smectic phase. Photopolymerizability of acryl and diacetylene groups was investigated by IR spectroscopy. An anisotropic polymer film could be prepared by selective polymerization of acryl groups with 365 nm UV light in the presence of a photoinitiator (2,2-dimethoxy-2-phenylacetophenone). The subsequent reaction of diacetylene groups with 254 nm UV light disrupted the anisotropic structure, suggesting that these LC molecules could be used for imaging on the film.

【 授权许可】

Unknown