Selective sorting of polymers with different terminal groups using metal-organic frameworks

Benjamin Le Ouay; Chikara Watanabe; Shuto Mochizuki; Masayoshi Takayanagi; Masataka Nagaoka; Takashi Kitao; Takashi Uemura

doi:10.1038/s41467-018-06099-z

Selective sorting of polymers with different terminal groups using metal-organic frameworks

Nat Commun. 2018 Sep 7;9(1):3635. doi: 10.1038/s41467-018-06099-z.

Authors

Benjamin Le Ouay^{1

2}, Chikara Watanabe³, Shuto Mochizuki³, Masayoshi Takayanagi^{2

4

5}, Masataka Nagaoka^{2

6}, Takashi Kitao^{1

2

7}, Takashi Uemura^{8

9

10}

Affiliations

¹ Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8561, Japan.
² CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan.
³ Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto, 615-8510, Japan.
⁴ The Center for Data Science Education and Research, Shiga University, 1-1-1 Banba, Hikone, Shiga, 522-8522, Japan.
⁵ RIKEN Center for Advanced Intelligence Project, 1-4-1 Nihonbashi, Chuo-ku, Tokyo, 103-0027, Japan.
⁶ Department of Complex Systems Science, Graduate School of Informatics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, 464-8601, Japan.
⁷ Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
⁸ Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba, 277-8561, Japan. t-uemura@k.u-tokyo.ac.jp.
⁹ CREST, Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan. t-uemura@k.u-tokyo.ac.jp.
¹⁰ Department of Applied Chemistry, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan. t-uemura@k.u-tokyo.ac.jp.

Abstract

Separation of high-molecular-weight polymers differing just by one monomeric unit remains a challenging task. Here, we describe a protocol using metal-organic frameworks (MOFs) for the efficient separation and purification of mixtures of polymers that differ only by their terminal groups. In this process, polymer chains are inserted by threading one of their extremities through a series of MOF nanowindows. Selected termini can be adjusted by tuning the MOF structure, and the insertion methodology. Accordingly, MOFs with permanently opened pores allow for the complete separation of poly(ethylene glycol) (PEG) based on steric hindrance of the terminal groups. Excellent separation is achieved, even for high molecular weights (20 kDa). Furthermore, the dynamic character of a flexible MOF is used to separate PEG mixtures with very similar terminal moieties, such as OH, OMe, and OEt, as the slight difference of polarity in these groups significantly changes the pore opening kinetics.

Publication types

Research Support, Non-U.S. Gov't