Melamine-barbiturate/cyanurate binary organogels possessing rigid azobenzene-tether moiety.
Melamine-barbiturate/cyanurate binary organogels possessing rigid azobenzene-tether moiety.
复制标题
DOI：
10.1021/la052076k
复制
发表时间：
2005-10
期刊：
影响因子：
--
通讯作者：
S. Yagai;T. Karatsu;Akihide Kitamura
中科院分区：
文献类型：
--
作者：
S. Yagai;T. Karatsu;Akihide Kitamura
二元有机凝胶由偶氮苯系三聚氰胺二聚体和氰尿酸盐/巴比妥酸盐的共聚集体制备。在烃类液体的凝胶中，共聚集体形成了严重缠结的纳米纤维，其形态与先前报道的基于柔性十二亚甲基束缚三聚氰胺二聚体的共聚集体显着不同。在本系统中，偶氮苯系链的刚性可以诱导分子的规则堆积。此外，紫外可见分光光度计和红外分光光度计测量分别为系链部分中的中心酰胺基团和偶氮苯发色团通过氢键和面对面（H型）pi-pi堆积相互作用形成明确的纳米纤维的贡献提供了明确的证据。由于自组装纳米纤维中分子紧密堆积，凝胶态的偶氮苯部分在紫外光照射下表现出显着的反式->顺式异构化抵抗能力。
Binary organogels were prepared from coaggregates of azobenzene-tethered melamine dimer and cyanurate/barbiturates. In the gels of hydrocarbon liquids, the coaggregates formed heavily entangled nanofibers, morphologies of which are dramatically different from the previously reported coaggregates based on flexible dodecamethylene-tethered melamine dimers. In the present systems, the rigidity of the azobenzene tether may induce regular packing of molecules. In addition, UV-vis and IR spectroscopic measurements provided unequivocal evidence for the contribution of the central amide groups and the azobenzene chromophores in the tether moiety upon forming well-defined nanofibers by hydrogen-bonding and face-to-face (H-type) pi-pi stacking interactions, respectively. As a result of tight molecular packing in the self-assembled nanofibers, the azobenzene moiety in the gel state showed remarkable resistance to trans --> cis isomerization upon irradiation with UV light.