New Coordination Polymer with Dynamic Channels Which Responds to Temperature Variation

Coordination polymers with porous framework structure have recently been spotlighted in our daily life. For example, activated carbon and zeolite are well known as inorganic porous materials. Activated carbon is widely used around us for air cleaning, deodorant, and the improvement of reactive substrate since it absorbs organic materials which correspond to its size. Similarly, zeolite is utilized as the catalyst in the process of refining petroleum.

These inorganic materials form relatively stable framework against heat. Due to the strong combination, however, it holds various disadvantages; one typical disadvantage is that it is difficult to form a flexible framework, which has prevented us from improving the chemical characteristics in the pores and changing the size or shape of them.

We have succeeded in the synthesis of the coordination polymer with dynamic channels for the first time worldwide. The structures change reversibly depending on the temperature variation. As the figure above shows, it makes a reversible change according to the decrease and increase in temperature. Using the single-crystal X-ray structure analysis, we captured the channel narrowing in low temperature.

Coordination polymer has been attracting intense attention these days as the new procedure to form a porous structure such as zeolite. It is a metal coordination compound, in which organic materials bridge between metals to form infinite structures.

Our aim is the synthesis of coordination polymers with dynamic channels, which change their structures in response to the physical stimuli by composing the pore structure based on a flexible framework.

Zeolite

Normal temperature

-40℃

Partial structure of coordination polymer, which changes reversibly depending on the temperature variation