But the Penn State University professor of agricultural and biological engineering in the College of Agricultural Sciences faced a problem. His formula of cellulose from wood and cotton and chitin derived from the exoskeletons of arthropods and such crustaceans as lobsters, crabs and shrimp, just wouldn’t mix. It kept separating. Driving his car and pondering a solution, the professor was staring at the pavement ahead when he realized the solution. He was staring at it. “I was looking at the blacktop and remember when I was a college intern at (The Pennsylvania Department of Transportation), which was using bituminous asphalt that had to be mixed with high-shear mixtures of oil, polymers and water,” he said. “Oil and water don’t mix but if you blend them at ultra high shear, they will form a solution or emulsion.” Milk, for example, is an emulsion of fat and water. Back at his lab, colleagues watched a bit dubiously, he said, as he put the components into a food blender and mixed them at high speed before applying the emulsion to a test surface. It was a eureka moment. The mixture he’d worked on for years formed a waterproof coating that he’d hoped to create, That product, with its multiple potential uses, is described in a recent study published in the Green Chemistry Journal. A cheaper, safer material for food packaging was his primary goal, with sustainability motivating him to develop the all-natural material that still lacks a name. Its components include cellulose pulp from wood or cotton and a material known as chisosan, derived from chitin, a main component of exoskeletons of insects and crustaceans. Cellulose, the main component of wood, is one of the most readily available materials on the planet, Mr. Catchmark said. He now is seeking a patent on the material, which he said could be used in wood-fiber composites for flooring, impervious films and industrial coatings and adhesives. It also could replace formaldehyde-based adhesives in many construction materials as well as uses in eco-friendly cosmetics. “The potential reduction of pollution is immense if these barrier coatings replace millions of tons of petroleum-based plastic associated with food packaging used every year in the United States and much more globally,” he said in a statement describing his new product. Plastic long has raised concern as food packaging including its use to line aluminum cans. Bisphenol A, a component of such plastics, has been linked with health impacts. The U.S. Food and Drug Administration recently granted two petitions requesting the administration to amend its food additive regulations to no longer provide for the use of certain BPA-based materials in baby bottles, sippy cups and infant formula packaging. These uses, the FDA said, “have been abandoned” as a result of controversy over their use. In the meantime, the FDA said, “Studies have raised questions about the safety of ingesting the low levels of BPA that can migrate into food from food contact materials. To address these questions the National Toxicology Program, partnering with FDA’s National Center for Toxicological Research, is carrying out in-depth studies to answer key questions and clarify uncertainties about BPA.” Plastics have other problems. Global production is approaching 300 million tons per year, with about 10 percent ending up as municipal solid waste, half of which is packaging. “It is anticipated that 10 percent of all plastic produced globally will become ocean debris, representing a significant ecological and human health threat,” said Mr. Catchmark, who holds a doctorate in electrical engineering, in a statement about his product. Southern Champion Tray, a leading manufacturer of paperboard packaging including pizza boxes in Chattanooga, Tenn., already is testing the new material in its products. ___ Online: http://bit.ly/2yKxtHg ___ Information from: Pittsburgh Post-Gazette, http://www.post-gazette.com
Penn State creates food packaging material from wood, shells.