Figure 1. Conceptual diagram of this research
The Univ of Tokyo: Developed the thinnest plastic: 1 molecule thickness, polymer sheet
University of Tokyo:
Point of announcement
◆ Polymer sheets are used in various products.
It is extremely difficult to reduce the thickness down to the molecular level, and it has long been a challenge for chemists.
◆ Uses a porous metal complex (MOF) with pores at the molecular level as a template.
We have succeeded in synthesizing a large amount of polymer sheets with a thickness of only one molecule.
◆This polymer sheet is
Reveal that flexibility will increase significantly,
As a material for many functional materials, a wide range of potential applications have been demonstrated.
Summary of presentation:
Professor Uemura of the University of Tokyo:
By using “a nano-sized space created by molecules as a template”, we have developed “a method for synthesizing extremely thin polymer sheets accurately and in large quantities”.
In developing products that require higher performance and lighter weight, such as automobiles and smartphones, how thin a polymer sheet can be made is important.
Problems with conventional methods:
However, there are limits to how thin the film can be formed by general film-forming methods such as coating and stretching.
It is not possible to reasonably and mass-produce thin polymer sheets down to the molecular level.
Solution using MOF:
The research group of Professor Uemura
Porous metal complex (MOF, Note 1) with small molecular size gaps
By using it as a template for polymer synthesis,
We have developed a method for synthesizing a large amount of polymer sheets with only one molecule of thickness.
The thinnest polymer sheet in the world:
This is the thinnest polymer sheet in the world.
Interestingly, this polymer sheet was found to have different properties than conventional polymers.
Properties different from macromolecules:
A general polymer has a string-like molecular structure and is entangled with each other.
However, polymer sheets cannot be intertwined in principle.
It has been discovered that it exhibits very flexible properties not previously known.
Large supply of sheet polymer:
This method will lead to the large-scale supply of sheet polymers, which was a dream material.
Polymer products,
Fats and oils,
paint,
Coating materials, etc.
It can be widely applied to all chemical products industries (Fig. 1).
http://www.k.u-tokyo.ac.jp/info/entry/22_entry890/
Unimolecularly thick monosheets of vinyl polymers fabricated in metal–organic frameworks
Nobuhiko Hosono, Shuto Mochizuki, […]Takashi Uemura
Nature Communications volume 11, Article number: 3573 (2020)
Abstract
Polymers with two-dimensional (2D) network topologies
are currently gaining significant attention due to their unique properties that originate from their regulated conformations.
However, in contrast to conventional 1D- and 3D-networked macromolecules, the synthesis of such 2D networks
provides challenges for polymer chemists because of the nature of the networking polymerisation reaction, which occurs in a spatially random fashion when conventional solution-phase synthesis is performed.
Here we report a versatile synthesis of polymeric monosheets with unimolecularly thick networking architectures by exploiting the 2D nanospaces of metal–organic frameworks (MOFs) as reaction templates.
Crosslinking radical polymerisation in the 2D nanospaces of pillared-layer-type MOFs affords monosheets of typical vinyl polymers and can be carried out on the gram scale.
Remarkably, the prepared polymer monosheets
are
highly soluble in organic solvents and show atypical thermal
and rheological properties that result from their 2D-regulated conformations that cannot be adopted by their 1D or 3D analogues.
Nature Communications