Here's the full article from Nature:
https://inf.news/en/science/58a6db9ad86d021d57f743d74c0df4a8.htmlCouple of interesting quotes:
The final reaction, using commercially available cheap trimesoyl chloride and melamine as reaction raw materials, was carried out in a strong hydrogen bond acceptor solvent such as NMP, and the obtained yellow solid powder was named 2DPA-1 (Fig. 3a). It is worth mentioning that the reaction is carried out at room temperature and normal pressure, and the operation is simple and convenient. It only needs to simply mix and stir the reactants, even without strict anhydrous and oxygen-free operation. Easily scale up to tens of grams in the lab.
It appears cheap trimesoyl chloride and melamine might be ingredients in Kevlar and some nylons, such as the PA-6 family.
2DPA-1 is insoluble in conventional organic solvents and water, but is soluble in strong acid (trifluoroacetic acid, pK a = 0.3) to form a clear solution. Nanofilms can then be formed on flat substrates with a simple spin coating (Fig. 4a). These films are precisely adjustable in thickness and their size is limited only by the size of the spin coater. In addition, the films can also be easily transferred to different substrates (silicon wafers with microporous structures or copper foils with openings) (Fig. 4b), or repeatedly stacked to show clear and uniform interference colors ( Figure 4c). In order to better demonstrate the transferability of the film, the authors prepared and transferred a film with a diameter of 6 inches and a thickness of 7 nanometers. 4e). SEM and AFM studies revealed that these spin-coated films produced exceptionally flat surfaces (Fig. 4f), with roughness generally less than 1 nm, and even as low as 0.3 nm. This means that in the micrometer range, the difference between the highest and lowest points of the membrane is only about four molecular heights.
this two-dimensional film is expected to exhibit ultra-high mechanical properties and become a two-dimensional version of Kevlar. The authors used nanoindentation to measure a series of self-supporting nanofilms (Figure 7), and the average Young's modulus of the nanofilms was measured to be 12.7 GPa, which is much higher than that of conventional polymers (2-4 GPa). At the same time, the yield strength of the material is as high as 488 MPa, which is about twice that of conventional structural steel, and the specific strength is about twelve times (simulations show that the density of 2DPA-1 is 1/6 of that of steel).
Notably, the material exhibited good puncture resistance during measurement and could withstand repeated failures without cracking. Whether punching holes on the edges of the membrane (Fig. 7b) or repeatedly piercing the membrane during the measurement (Fig. 7c–d) did not affect its mechanical performance. This property has not been observed in common 2D materials such as graphene.
It was found that the addition of a small amount of 2D polymer was sufficient to significantly improve the mechanical properties of the fibers. For example, 6.9% volume fraction of 2DPA-1 increases the Young's modulus of PC fibers by 72%; at the same time, the tensile strength also increases from 110 MPa to 185 MPa (Fig. 8c).
So, yea, it's kind of an exciting material.....
