Superman would be jealous of this super-material, stronger than the Man of Steel himself
It’s as light as plastic, it’s tougher than steel, it’s…the polymer equivalent of Superman.
The impossible now exists. There is now a substance that has so much muscle that it is impermeable to gas, and even Clark Kent would be shocked by how much force he would need to break it: twice the force it takes to break steel. Known as 2DPA-1, the almost supernatural polymer could be the shield of the future for cars and machinery, and could potentially support entire buildings. Lex Luthor obviously has nothing on this.
MIT chemical engineer Michael Strano is the brains behind the (almost) unbreakable stuff. He coauthored a study, recently published in Nature, with postdoc Yuwen Zeng and a team of researchers who have taken polymers to the next level. Plastics are polymers — but still only mere mortals when compared to a polymer that can take on bulletproof glass. 2DPA-1 is now waiting on two patents for the process that creates it, so no supervillains can steal it.
“The hydrogen bonding of 2DPA-1 ensures that the layers grip each other out of plane, transferring the load to the whole solid,” Strano told SYFY WIRE. “In this way, even though it is a lightweight polymer, it can exhibit exceptional strength.”
2DPA-1 kind of works like Velcro. What makes Velcro grip isn’t any one particular loop and hook, but many of them grabbing onto each other at once. The super-polymer gets its abnormal strength from hydrogen bonds. Its monomers are made of melamine (which further breaks down into carbon and nitrogen atoms in a ring structure). They form platelets as they grow in 2D. The micro-platelet layers would slip to hold them together, and one hydrogen bond is far from enough, but many hydrogen bonds between the layers keep them stacked and in place.
Hydrogen bonds make sure that 2DPA-1 doesn’t lose its powers. Instead of the burden being on just one bond, which would be like expecting one hook and loop of Velcro to hold something shut, multiple bonds share the load throughout the polymer. Something similar happens with the platelets. Any random platelet would be permeable by gas because there are holes in its molecular structure. However, when these are stacked on top of each other and bonded by hydrogen in sheets of 2DPA-1, they cover each other’s holes and allow no molecules to enter.
“We don't detect any molecules entering the interior of the solid,” said Strano. “When we make a thin film of the material, we can't measure any gas permeation, so by our measurements, 2DPA-1 is the most effective barrier material of any organic polymer known.”
What is even more amazing about 2DPA-1 is that the polymer assembles itself. It only needs solution, and monomers stack into sheet form on their own. Strano thinks hydrogen bonding makes it easier for it to do this, and can only form through self-assembly. Monomers that stack themselves stay where they are, and in the right position to allow parallel monomers to attach to them. This is a type of autocatalysis that the researchers call autocatalytic templating. Autocatalysis happens when a chemical reaction is also a catalyst — it sets off another reaction.
So how strong is 2DPA-1? It’s easier to put a dent in bulletproof glass. Its elastic modulus, or how much force is needed to temporarily deform it, is up to six times more than that of glass that is supposed to be bulletproof and everything else-proof. You might otherwise know this property as elasticity. Steel might be six time denser, but to break steel, you still only need half the force you do to break 2DPA-1. The force needed to break something is yield strength. Like Superman, this polymer doesn’t yield very easily, and seems to have no kryptonite. Strano believes more might come out of it.
“We were able to make composites and fibers for testing right away,” he said. “New applications such as coatings and membranes are being investigated currently. Because we can change the monomer composition, we should be able to tune its properties.”
Maybe 2DPA-1 isn’t a bird or a planet, but it might someday be the protective coating on a plane — or a rocket that goes all the way to Krypton.
