New experimental polymers could deliver cheaper, lighter, stronger and recyclable materials ideal for electronics, aerospace, airline and automotive industries.
Through the unique approach of combining high performance computing with synthetic polymer chemistry, these new materials are the first to demonstrate resistance to cracking, strength higher than bone, the ability to reform to their original shape (self-heal), all while being completely recyclable back to their starting material. Also, these materials can be transformed into new polymer structures to further bolster their strength by 50% – making them ultra strong and lightweight.
IBM’s discovery with a host of tunable and desirable properties provides a new opportunity for exploratory research and applications development to academia, materials manufacturers and end users of high performance materials. Two new related classes of materials have been discovered which possess a very distinctive range of properties that include high stiffness, solvent resistance, the ability to heal themselves once a crack is introduced and to be used as a resin for filled composite materials to further bolster their strength.
The ability to selectively recycle a structural component would have significant impact in the semiconductor industry, advanced manufacturing or advanced composites for transportation, as one would be able to rework high-value but defective manufactured parts or chips instead of throwing them away. This could bolster fabrication yields, save money and significantly decrease microelectronic waste.
James Hedrick, Advanced Organic Materials Scientist, IBM Research said;
Although there has been significant work in high-performance materials, today’s engineered polymers still lack several fundamental attributes. New materials innovation is critical to addressing major global challenges, developing new products and emerging disruptive technologies. We’re now able to predict how molecules will respond to chemical reactions and build new polymer structures with significant guidance from computation that facilitates accelerated materials discovery. This is unique to IBM and allows us to address the complex needs of advanced materials for applications in transportation, microelectronic or advanced manufacturing.
These new polymers are formed from the same inexpensive starting material through a condensation reaction, these molecules join together and lose small molecules as by-products such as water or alcohol and were created in an operationally simple procedure and are incredibly tunable.
At high temperatures (250 degrees Celsius) the polymer becomes incredibly strong due to a rearrangement of covalent bonds and loss of the solvent that is trapped in the polymer (now stronger than bone and fibreboard), but as a consequence is more brittle (similar to how glass shatters).
Remarkably, this polymer stay intact when its exposed to basic water (high pH), but selectively decomposes when exposed to very acidic water (very low pH). This means that under the right conditions, this polymer can be reverted back to the starting materials, which enables it for reuse for other polymers. The material can also be manufactured to have even higher strength if carbon nanotubes or other reinforcing fillers are mixed into the polymer and are heated to high temperatures. This process enables polymers to have properties similar to metals, which is why these “composite blends” are used for manufacturing in airplane and cars. An advantage to using polymers in this case over metals is that they are more lightweight, which in the transportation industry translates to savings in fuel costs.
At low temperatures (just over room temperature), another type of polymer can be formed into elastic gels that are still stronger than most polymers, but still maintains its flexibility because of solvent that is trapped within the network, stretching like a rubber band.