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Opening of an Accessible Microporosity in an Otherwise Nonporous Metal–Organic Framework by Polymeric Guests
Version 2 2017-05-30, 17:04
Version 1 2017-05-24, 18:50
journal contribution
posted on 2017-05-16, 00:00 authored by Benjamin Le Ouay, Susumu Kitagawa, Takashi UemuraThe development of highly porous
metal–organic frameworks
(MOFs) is greatly sought after, due to their wide range of applications.
As an alternative to the development of new structures, we propose
to obtain new stable configurations for flexible MOFs by insertion
of polymeric guests. The guests prevent the otherwise spontaneous
closing of the host frameworks and result in stable opened forms.
Introduced at a fraction of the maximal capacity, polymer chains cause
an opening of the occupied nanochannels, and because of the MOF reticular
stiffness, this opening is propagated to the neighboring nanochannels
that become accessible for adsorption. Composites were obtained by
in situ polymerization of vinyl monomers in the nanochannels of an
otherwise nonporous MOF, resulting in homogeneously loaded materials
with a significant increase of porosity (SBET = 920 m2/g). In addition, by limiting the accessible
configurations for the framework and forbidding the formation of a
reactive intermediate, the polymeric guest prevented the thermal degradation
of the host MOF even at very low loading (as low as 3 wt %) and increased
its stability domain by more than 200 °C.