I may have ruined dinner for someone awhile back. It all began when table conversation at a dinner party turned to coffee shops and, more specifically, disposable coffee cups. The woman on my right was convinced the paper cup she used for her morning latte was completely recyclable and should go in a recycle bin. Well, just call me Dougy Downer. I had to explain to her that her disposable coffee cup has a plastic coating that gums up the works at paper-recycling plants. So billions of coffee-shop cups get diverted to landfills before they get anywhere near a recycling facility.
A lot of people have the same misconception as my dinner companion. They also don’t realize it isn’t just paper coffee cups that end up in the dump. Ice-cream containers, frozen-food packages, paper trays for produce, and similar paper containers that come in contact with food all have a low-density polyethylene (LDPE) coating inside and out. Paper mills that attempt to recycle these items find the plastic breaks down only into relatively large chunks that are incompatible with reducing paper back into pulp. So most of this packaging winds up discarded somewhere.
Fortunately, technological advances in the works could make disposable cups and food packaging more recyclable. One such development comes from Smartplanet Technologies, which has come up with a mineralized polyolefin coating that replaces LDPE. We were impressed enough with Smartplanet’s idea to do a video about it on EngineeringTV.com.
In our interview, Smartplanet Chief Technology Officer Chris Tilton told us when cups coated with the stuff go to a paper mill, the plastic contamination from the coating is small enough and dense enough to be filtered out of paper fibers. The point is to make the resulting coating go through the recycling process more like a mineral than like a plastic. But Smartplanet’s coating can be applied with existing equipment normally used for LDPE. The thermal properties of the minerals they add are such that coatings of their substance can go on at the same superhigh speeds as used for conventional LDPE.
Another idea aimed at keeping disposable cups out of landfills comes from Berry Plastics Group Inc. Announced last fall, Berry’s approach eliminates the plastic coating completely by making cups out of No. 5 plastic polypropylene, a material which many facilities recycle. The material is a good insulator so it can replace disposable foam cups. The thermal performance of the cup, called Versalite, comes from a proprietary technology that involves infusing a cellular structure into a base of polypropylene. Besides being fully recyclable, the new cup can be put in a microwave and is reusable many times, even after numerous trips through a dishwasher. Berry says the durability comes from not only the polypropylene but also from the use of construction methods not normally employed on paper and foam cups.
Thanks to developments like these, we may soon see a day when there are fewer disposable cups in landfills, and fewer awkward moments at dinner parties.