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Updated: Jun 5, 2025
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Mechanically induced polyamorphism in a one-dimensional coordination polymer
Taichi Nishiguchi1, Yuki Ohara1, Kentaro Kadota2
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University Katsura, Nishikyo-ku Kyoto 615-8510 Japan.
Abstract:
We created different amorphous structures of a coordination polymer by applying mechanical shear forces. One-dimensional Cu(Tf2N)2(bip)2 (1, Tf2N- = bis(trifluoromethanesulfonyl)imide, bip = 1,3-bis(1-imidazolyl)propane) melted at 245 °C and underwent a glass transition at -10 °C by a static cooling process. 1 formed another amorphous state with a distinct glass transition point of 70 °C under oscillatory shear stress. The difference of orientation in their structures was studied by X-ray absorption fine structure and small-angle X-ray scattering. The reversible transition between the two amorphous states was observed by dynamic mechanical analyses.
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