2006 Fiscal Year Final Research Report Summary
Development of New Photo-triggered Mass Transport Systems
| Project/Area Number |
16205019
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Functional materials chemistry
|
|---|
| Research Institution | Nagoya University |
|---|
Principal Investigator |
SEKI Takahiro Nagoya University, Graduate School of Engineering, Professor (40163084)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NAGANO Shusaku Nagoya University, Graduate School of Engineering, Assistant Professor (40362264)
TAKEOKA Yukikazu Nagoya University, Graduate School of Engineering, Associate Professor (20303084)
UBUKATA Takashi Yokohama National University, Graduate School of Engineering, Assistant Professor (00344028)
|
|---|
| Project Period (FY) |
2004 – 2006
|
| Keywords | mass transport / azobenzene / block copolymers / hierarchical strucures / relief formation / molecular orientation / hydrogen bonding |
|---|
| Research Abstract |
Az polymers are potentially useful as materials for reversible holographic information storage and photonic devices. Surface relief gratings (SRG) formed via irradiation with an interference pattern of coherent light have been demonstrated. We have developed highly sensitive photo-activated mass migration systems using LC binary component materials comprised of an azopolymer and a liquid crystal molecule or azopolymers containing a soft segment. The energy level is three orders of magnitude smaller than those required for conventional amorphous polymer systems hitherto reported. This efficient migration is found to be due to the photoinduced phase transition of a smectic phase to an isotroipic one. In the our migrating system, the quick motion itself can be a valuable function. An application as a "molecular conveyer" for patterning of light-inert (non-photoresponsive) functional materials can be presented. Functional materials, such as dye molecules, conjugated polymers, and semiconductor quantum dots, can be conveyed by the massive motion of the Az polymers. Azobenzene unit is essential for the photo-induced mass migration, but after the relief formation the existence of this strongly light absorbing chromophore will be a severe drawback for many optical applications. To overcome these contradictory requirements, a system in which the Az unit can be detached after the relief formation is proposed. Here the Az unit is not necessarily linked to the polymer backbone, but the supramolecular liquid crystalline framework via hydrogen bonding (Kato system) is applied. After the crosslinking mentioned above, the Az unit is readily removed from the film with retention of the morphological feature of the relief structure. The present proposal can be a facile and versatile method for bleaching the SRG film.
|
