San Jose, CA — A new development by IBM Research and Stanford University could lead to plastics that can be recycled multiple times - and at lower temperatures - and a new type of biodegradable plastic.
Researchers from IBM's Almaden Research Center in San Jose and Stanford have created new organic catalysts that can be used to create and break down plastics instead of using the typical metal catalysts.
When plastics are made with metal catalysts, some heavy metals can get left in the plastic, contaminating and degrading it, affecting the material's recyclability. When most plastic is recycled, it can only go through the recycling process once, in the case of a soda bottle being turned back into a new soda bottle. But that new material is no longer recyclable like it once was.
Organic catalysts, on the other hand, do not leave harmful residue in the plastic, are able to break the polymers in plastics down to their original state, and are cheap to produce.
"It could lead to a new recycling process that reverses the polymerization process to regenerate monomers in their original state. Conceivably, this could mean that you could recycle the same materials over and over," said James Hedrick, leader researcher on the project at IBM Research-Almaden.
The organic catalysts provide additional benefits during plastic recycling. They can break down plastics at room temperature, compared to the high temperatures and energy used by current recycling processes. The organic catalysts could also be used in the creation of bioplastics.
The King Abdulaziz City for Science and Technology in Saudi Arabia is working with IBM and Stanford to set up a pilot recycling program for PET (the common plastic used in drink bottles, identified with the resin code 1) using the organic catalysts.
While the breakthrough could lead to bottles that can be recycled over and over, the researchers are also looking at other possibilities for the organic catalysts, such as in healthcare and microelectronics.
For instance, they could be used in drug delivery devices, since the organic catalysts would not be harmful in a human body.
The researchers are particularly looking at drug delivery for cancer patients, since many cancer-fighting drugs also go after healthy cells. The use of organic catalysts, the researchers say, could lead to new custom polymers that can help deliver drugs to specific cells or regions.
The research team's findings are published in the American Chemical Society's Macromolecules journal.