A two-year collaboration between a recycler, an extruder and the University of Wisconsin is on the verge of bringing to market a mixed resin made from post-consumer electronics that they say is suited for construction, packaging and industrial use.
The breakthrough also creates a way to compound a mix of waste, rather than have to separate the materials.
The official thumbs up for the project is about a month away. When it starts, production of the mixed resin - developed with the help of the UW Polymer Engineering Center - will give Cascade Asset Management LLC of Madison, Wis., a higher net price for the material it had been shipping to China. It also will give Pro Ex Extrusion Inc. of Oshkosh, Wis., a resin it potentially can use in combination with virgin material, instead of all-virgin PVC in some construction applications.
Cascade's profit when it was shipping the plastic computer scrap overseas was 2-4 cents per pound, according to center director Tim Osswald and graduate student Michael Dattner. In China, the material was used to reinforce corners for luggage.
Now, Pro Ex is paying Cascade 12-14 cents per pound for the scrap. The firm compounds it and makes profiles that it can sell for 30-34 cents per pound.
``We are still very much in an experimental stage, and there is a chance the whole project will go by the wayside, but this material has some viability [and] is close to meeting the standards needed'' for several commercial applications, said Pro Ex President Gary Borgers. ``We'll know by July 1.''
The resin will contain 70-80 percent ABS; much of the rest will be high-impact polystyrene.
``I thought there had to be a better way,'' said Neil Peters-Michaud, chief executive officer of Cascade Asset, a 7-year-old company that initiated the project to make resins from post-consumer electronics. The company did not want to hand-sort the material or use a spectrometer that accommodates three or fewer types of resin and rejects two-thirds of the plastic.
``The main challenge was on the processing side, to see if metals could be removed using 2- to 5-millimeter screens typical to any shredding operation, and to see if you can get a product out of nonhomogenous materials,'' he said. ``This allows demanufacturers to continue their current disassembly operations with no additional sorting requirements ... while providing up to three times more value for their recycled plastic.''
Since December, Cascade has been shipping the 80,000 pounds of plastics it typically recovers and bales each month from computers, monitors, laptops, printers, keyboards and televisions to Pro Ex to grind and compound. Plastics are just over 10 percent of the 750,000 pounds of material Cascade recycles monthly, primarily in the three-state area of Wisconsin, Minnesota and Illinois.
Both firms now have new equipment in place for the project, thanks to a grant from the Wisconsin Department of Natural Resources. Cascade has an Excel EX-62 automatic-feed baler, 17 tip carts and 16 workstations, said Peters-Michaud. The new machine has increased the amount of plastics it can put in a bale by 200 pounds, he added.
Borgers declined to be specific about the processing equipment Pro Ex added in April, but other sources said the company purchased shredders, Eddy current separators, granulators and magnetic separators for the new compounding operation.
Borgers declined to name specific potential end markets, saying only that, so far, the company has targeted four construction applications in which the resin would be a replacement for virgin PVC.
``We are trying to keep the number small. We want to see how it works in a few specific applications first,'' he said.
A source close to the project said one of the products is a slide used to pour concrete.
Tests by both UW Polymer Engineering Center and Pro Ex have showed the resin mix to have consistent levels of tensile strength, bendability, melt flow and processability, according to Osswald, who helped develop the compounding method.
The material is better than polystyrene, but not as tough as ABS, Osswald said. He noted that additives such as rubber modifiers should be used to improve impact resistance, when needed.
Borgers said Pro Ex is experimenting with impact modifiers, as ``the material is very brittle.''
He said other primary concerns are the materials' cleanliness and making sure products made from the resin ``meet the aesthetic and physical characteristics needed.''
Using the mixed recycled resin ``will only give us an advantage if it is a lower-cost material and performs within the specifications of the product,'' Borgers said.
``It is a competitive marketplace, so the low-price material that works best will win.''
Pro Ex's goal is to make and sell the compound. ``If our data is correct, there would be enough material available'' that 50 percent of the resins could be sold to other companies. Beyond construction, Borgers said the resin could be used in packaging applications, if density issues can be overcome, and wheelchair makers are looking at framework and nonstructural uses.
Osswald said the resin could be used in lighting fixtures and electronics housings. He has talked to Bemis Manufacturing Co. of Sheboygan Falls, Wis., about using the resin with virgin materials for toilet seats and body panels for tractors.