IBM Researchers recently discovered a new class of polymer materials that offer the potential to transform manufacturing and fabrication in the fields of transportation, aerospace and microelectronics.
This material is a thermoset, which means it is very stable in terms of both temperature and mechanical properties, and typically can’t be recycled because once it has been molded it is not reversible. Using a 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.
According to IBM, the ability to selectively recycle a structural component made from this new polymer material 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.
“Remarkably, this polymer remains intact when it is exposed to basic water (high pH), but selectively decomposes when exposed to very acidic water (very low pH),” IBM said in a press release. “This means that under the right conditions, this polymer can be reverted back to its 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 airplanes 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 from this material: an elastic gel that is stronger than most polymers, but still maintains its flexibility because of solvent that is trapped within the network, stretching like a rubber band. One of the most amazing features of these gels is that “if they are severed and the pieces are placed back in proximity so they physically touch, the chemical bonds are reformed between the pieces making it a single unit again within seconds. This type of polymer is called a “self healing” polymer because of its ability to do this.
While not presently available commercially, this new material is expected to have a great future in many different industries.