ELIZABETH TENNYSON
Associated Press Writer
Raleigh (AP) – Does your soda go flat? Is the gas tank on your car corroding? Are your wine bottles to heavy?
If so, researchers at North Carolina State University may have the solution to your problems.
Chemical engineers at the school are working on a strain of liquid crystalline polymer plastic that could seal in flavor and carbonation while keeping out air. The plastic could also be used to stop corrosion of fuel tanks and underground power lines.
“The main science behind it is these polymer molecules pack very well,” said Chris McDowell, a doctoral student working on the project. “The molecules are long and stiff like a pen. That allows them pack together so there is no room for small molecules like oxygen to pass through.”
Beer and wine are extremely sensitive to oxygen and quickly lose their flavor if air gets into the packaging. But the new variety of plastic, known as PICT, could keep enough oxygen out to make plastic beer and wine containers practical.
The plastic also could be used to extend the shelf life of bottled soda, which now keeps for six to eight weeks, and to make smaller, 12-ounce, soda bottles. Existing plastic bottles, which are made from another kind of plastic called PET, can be used to hold only 16 or more ounces of soda.
“Due to how fast these small molecules migrate through PET polymers, you cannot have small packages, ” McDowell explained. “It has to do with the amount of surface area in the smaller packages.”
Dr. Benny Freeman, associate professor of chemical engineering, presented the team’s findings Monday at the American Chemical Society’s annual meeting in New Orleans.
Researchers are uncertain how long commercial development of their plastics might take, but estimate the new food bottles could appear on store shelves within the next decade. The process is expensive now, but Freeman believes his group’s work will pave the way for cost-effective production of food containers and specially coated underground cables.
“Underground electric power cables with a thin coating of these plastics would have substantially longer lifetimes than non-coated cables because of the prevention of moisture ingress and subsequent corrosion,” Freeman said. “Yet adding the coating only adds about one cent per foot to the total production cost.”
Freeman also hopes the plastic will be used to make lightweight, corrosion resistant fuel tanks for cars running on reformulated gasoline.
The project is currently funded by the National Science Foundation and the chemical company Hoechst Celanese.
