(Liq. Cryst.) Photo-Responsive Polysiloxane-Based Azobenzene Liquid Crystalline Polymers Prepared by Thiol-Ene Click Chemistry
作者:Wang, M.; Guo, L.; Lin, B.; Zhang, X.; Sun, Y. Yang, H.*
关键字:Liquid Crystal
论文来源:期刊
具体来源:Liquid Crystals, 2016, 43, 1626-1635.
发表时间:2016年
In this work, a novel polysiloxane-based azobenzene-containing liquid crystalline polymer (LCP) PMMS-A44V6 are designed and synthesized via a facile thiol-ene click chemistry method by grafting a side-on azobenzene mesogenic group A44V6 onto poly-[3-mercaptopropylmethylsiloxane] (PMMS) backbone. 1H NMR, 13C NMR, GPC, TGA, DSC, POM and WAXS are used to investigate the mesogenic properties and photo-responsive behavior of PMMS-A44V6. Taking advantage of the azobenzene’s trans-cis isomerization effect, PMMS-A44V6 can perform an isotropization process under UV irradiation in its nematic phase. Initially, the isotropization process starts in a linear decrease manner with a rate of ca -6.5 × 105 intensity/s, and eventually finishes in an exponential decrease regime to form cis-azobenzene moieties. The reversible UV-response behavior of PMMS-A44V6 can be performed in a relatively low temperature range of 30 ~ 75 oC, which might help this azobenzene-containing LCP material to find potential application in control devices.