Fabrication of Nanocrystals from Diolefin Derivatives and Their Solid-State Photoreaction Behavior
作者:Hirohiko Miura、Shu Takahashi、Hitoshi Kasai、Shuji Okada、Kiyoshi Yase、Hidetoshi Oikawa、Hachiro Nakanishi
DOI:10.1021/cg900511z
日期:2010.2.3
Nanocrystals of seven p-phenylenediacrylates, i.e., dimethyl (1a), didecyl (1b), diundecyl (1c), ditetradecyl (1d), dipentadecyl (1e), dioctadecyl (1f), and dicholesteroyl (1g) derivatives, and 2,5-distyrylpyrazine (2) were fabricated by the re-precipitation method and their photochemical reaction behaviors were investigated in comparison to those of bulk crystals. The bulk crystals of 1a-1c and 2 were found to be photoreactive, whereas those of 1d-1g were less photoreactive. In contrast, all of the nanocrystals of 1a-1g and 2 showed high photoreactivity. Nanocrystals of 1a and 2 were demonstrated to have the same packing as the corresponding polymerizable bulk crystals, and they gave the corresponding polymers by photoirradiation. The polymer crystal structures in their nanocrystals were confirmed to be the same as those in bulk crystals by X-ray and electron diffraction analyses. Their single-crystal-to-single-crystal transformation was established by their nanocrystallization. On the other hand, other nanocrystals (1b-1g) were found to have different packings compared with the corresponding bulk crystals. After photoirradiation, their crystallinity was degraded to form amorphous products.