longest effective -conjugation length was obtained for the gel
state of 2, and its structure was found to disorder during the dry-
ing process. Since structural difference between 1 and 2 is only
the direction of the amide groups, most of physical properties
were found to be the same. However, polymerization behaviors
sensitive to the arrangement of the polymerization site were al-
tered. Compound 3 has higher gelation ability than others be-
cause of structural flexibility around the amide groups, which is
responsible for intermolecular hydrogen bondings. Due to the
molecular design with amide and TDP groups, all compounds
gave gels in various organic solvents. From SEM observation, it
was found that differences in transparency of the gels were
mainly originated from differences in the nanofiber diameters.
From these results, solid-state conditions of this type of com-
pounds seems to be carefully controlled to obtain the uniform
structure with desired properties.
Tomita for their experimental works at the initial stage of this
study.
Supporting Information
The absorption maximum wavelengths of the polymers,
the melting points of the monomers and the synthesis procedures
and the spectroscopic data of the related compounds are summa-
rized in Supporting Information.
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Acknowledgement
The authors thank to Mr. Rintaro Takahashi and Mr. Ryohei