LAS VEGAS — The winner of the Society of Plastics Engineers' top honor, the International Award, professor Avraam Isayev, outlined work in ultrasonics to recycle rubber and crosslinked polyethylene film, through a process of decrosslinking, in a presentation April 28 at Antec 2014.
Isayev and other award winners were honored with a banquet before Antec began in Las Vegas. He presented a technical paper outlining his work on ultrasonic processing during an Antec session.
“This ultrasonic recycling can work for any type of rubber — EPDM, tires etc.,” he said.
Isayev is distinguished professor of polymer engineering at the University of Akron, where he also served as interim director of the Institute of Polymer Engineering and Director of the Molding Technology Research and Development Center.
He discovered, developed and patented the ultrasonic extrusion process for the devulcanization of tires, helping solve a major national problem of scrap tires. Among other innovations, he did fundamental studies on high-power ultrasonic-assisted extrusion for in-situ copolymer formation and compatibilization of blends of immiscible polymer in the melt state, and the dispersion of nanofillers to make nanocomposites, using ultrasonically-assisted extrusion processes.
Isayev's talk was titled Environmental Sustainability Through Polymer Processing. He said the U.S. generates 300 million scrap tires every year. He said most are now burned for fuel, but likened that to burning money. It is far better to devulcanize the rubber, which is a thermoset, and then revulcanize it into new tires, he said.
But he said you need a great amount of energy to break the bonds of vulcanization. The key, he said, is to use the voids between the molecules, and eventually break the bonds.
Isayev recalled how researchers created an ultrasonic reaction extrusion system with a coaxial die, or one with the ultrasonics in the grooved barrel. Eventually, the pioneers developed an industrial sized machine.
They studied variables such as the materials' residence time in the machine.
Isayev also explained how ultrasonics works on crosslinked PE film. The resulting, decrosslinked material can be injection molded, but you cannot extrude it again, he said.
The International Award is the plastics industry's most prestigious annual award.
The Newtown, Conn.-based SPE announced other awards at Antec 2014: