Updated — IBM is out with a new way to recycle polycarbonates, and it's all thanks to Jeanette Garcia's musical tastes. In a roundabout way.
Garcia works at IBM Research's Almaden laboratory in San Jose, Calif., and wanted to build on previous company efforts to depolymerize PET.
The result is what the company calls a “new, one-step chemical process” that converts polycarbonates and prevents the leaching of bisphenol A, a controversial chemical used to manufacture that polymer.
While a detailed explanation is technical, Garcia found that the addition of a fluoride reactant, heat and a base similar to baking powder produces a new plastic that will not leach BPA. They call the new material polyaryl ether sulfone.
She teamed with fellow research staff member Gavin O. Jones in the project, with Garcia handling the hands-on laboratory work and Jones responsible for the computer work to help prove the process.
“I went into the lab one day and there's a stack of CDs that were sitting out that were from some previous interns that used to listen to them when they were working,” Garcia recalled.
“CDs are made out of polycarbonate, and so basically I took one of the CDs, I sorted through a few and made my judicious choice of which band I liked the least, and I won't tell you who it was, but I basically took that and cut it into pieces with scissors,” Garcia said.
With little pieces about 1 centimeter in size, the scientist got to work to create a way to depolymerize the PC.
The result was a new plastic powder with temperature and chemical resistance superior to the original substance, IBM said. “When the powder is reconstructed into new forms, its strength prevents the decomposition process that causes BPA leaching.”
Polycarbonates are already recycled through traditional mechanical methods — think sorting, washing and shredding. But IBM Research's work changes the chemistry of the material to allay BPA leaching concerns.
Garcia started her work on the PC project about three years ago. Her hope is that less material will be thrown away while creating a type of plastic that that can be used for water purification, fiber optics and medical equipment, for example.
IBM estimates that 2.7 million tons of PC is made around the world each year. And BPA widely came to the public's attention in 2008 when there were reports of the material leaching from baby bottles.
“IBM is not a chemical company. So in order to bring a technology like this from a proof of concept to the next level, we need to partner with people who are in the industry and interested in pursuing this,” Garcia said.
“My hope is really that we start thinking about plastics as being a resource for materials,” she said.
A research paper, entitled “One-step Conversion of Polycarbonates into Value–Added Polyaryl ether sulfones” has been published in a peer-reviewed journal, Proceedings of the National Academy of Sciences of the United States of America — PNAS for short.
“We now have a new way of recycling to improve how this prominent substance impacts the world's health and environment,” said Jones said in a statement.
Garcia and Jones are two of the five authors of the paper.
“We have a very rich history as far as materials development here. And in that bucket is also plastics and polymer synthesis, characterization and know-how that we've really built up over the decades in the semiconductor industry. So now we're basically taking insights that we've gained from that, we're applying it to new problems. We're applying it in new areas where it seems like it fits and where the technology works,” Garcia said.
