Assembling and orientation of polyfluorenes in solution controlled by a focused near-infrared laser beam.
Assembling and orientation of polyfluorenes in solution controlled by a focused near-infrared laser beam.
复制标题
DOI：
10.1021/jp0441184
复制
发表时间：
2005-03
期刊：
影响因子：
--
通讯作者：
Sadahiro Masuo;H. Yoshikawa;H. Nothofer;A. Grimsdale;U. Scherf;K. Müllen;H. Masuhara
中科院分区：
文献类型：
--
作者：
Sadahiro Masuo;H. Yoshikawa;H. Nothofer;A. Grimsdale;U. Scherf;K. Müllen;H. Masuhara
聚（2，7-（9，9-二（2-乙基己基）芴））的四氢呋喃溶液在玻璃基片上的干燥过程中，在聚焦近红外激光的作用下，可以形成有序的纤维状和颗粒状组装体。这些形成已经通过将激光照射与浇铸溶液中的对流相结合来可控地实现;也就是说，当对流中溶液的粘性阻力比光子力强时，可以形成原纤维状组装体。组装体中的分子取向与自组装纤维状结构中的分子取向不同，可能可以通过聚焦激光束的偏振方向来控制。我们已经证明，组件的长度和宽度可以通过照射时间，激光功率，溶液的浓度和溶液中的对流速率来控制。另一方面，当对流中的溶液的粘性阻力与光子力相比较弱时，形成其中分子取向由偏振方向控制的颗粒状组装体。
Ordered fibril- and particle-like assemblies of poly(2,7-(9,9-bis(2-ethylhexyl)fluorene)) can be formed by photon force of a focused near-infrared laser beam during the drying process of its tetrahydrofuran solution on a glass substrate. These formations have been achieved controllably by combining laser irradiation with convection in the cast solution; that is, when viscous drag of the solution in the convection is stronger than the photon force, the fibril-like assemblies can be formed. Molecular orientation in the assemblies differs from that in self-assembled fibril-like structures, and maybe it can be controlled by the polarization direction of the focused laser beam. We have demonstrated that the length and width of the assemblies can be controlled by the irradiation time, the laser power, the concentration of the solution, and the convection rate in the solution. On the other hand, when the viscous drag of the solution in the convection is weak compared to the photon force, particle-like assemblies in which molecular orientation is controlled by polarization direction are formed.