含偶氮苯基元联酰胺衍生物的有机凝胶和光响应性质

摘要

The hydrazide derivatives containing azobenzene groups N-(3,4-n-oxyphenyl)-N′-4-(azophenyl)-benzohydrazide Dn( n=7, 8, 10) with different terminal alkyl chain lengths were designed and synthesized. Dn can form a stable organogel and the terminal alkyl chains play crucial roles in improving the gel ability and thermodynamic stability. The main driving forces of gel formation are intermolecular hydrogen bonds between amide groups,π-πinteractions among azobenzene groups and van der Waals forces between alkyl chains. Irra-diation of the solution by UV light can lead to trans-cis isomerization of the azobenzene units. Although the con-version efficiency of cis-azobenzene in solution is notable, the photo-induced trans-cis isomerization of azoben-zene in the gel cannot induce gel-sol.%设计合成了具有不同末端烷基链长度的偶氮苯类联酰胺衍生物N-(3,4-n-氧基苯基)-N′-4-(偶氮苯基)苯甲酰肼(Dn,n=7,8,10).Dn可以形成稳定的有机凝胶,末端烷基链增加有利于提高凝胶能力和热力学稳定性.凝胶形成的驱动力主要为联酰胺基团间的分子间氢键以及偶氮苯基团间的π-π相互作用和烷基链间的范德华力.在紫外光照射下,Dn中的反式偶氮苯向顺式转化,并且在溶液中的光响应性非常显著,但凝胶态下偶氮苯的光致顺反异构不能诱导凝胶-溶胶的转变.