Plastic Coatings, Step Aside

Polyolefins are inexpensive, readily available, easily used in manufacturing, and provide performance as a barrier layer in paper and label packaging applications. On the down side, paper packaging with plastic coatings cannot easily be recycled with standard recovery equipment.

Despite the widespread collection infrastructure for packaging materials, recyclers typically decline to accept plastic coated cartons and cups and large quantities of those materials are diverted to landfill. The plastic layer creates processing problems at many recycling mills.

The cities of Portland, Oregon and Minneapolis, Minnesota do not accept plastic coated boards in their municipality recycling program for this reason. ‘A lot of poly coated stock is high value solid bleach board (SBS),’ explains Johnny Gold, senior VP of the recycled fibers division at Newark Recovery and Recycling. ‘It’s great fiber, but as soon as poly is on it, it’s contaminated. Recyclers shy away because it will clog up our systems without additional chemical and mechanical processing.’

Smart Planet Technologies has developed a way to mineralize commonly used plastic coatings, such that barrier-sealed boards can pass standard industry recycling tests. Georgia Tech’s Institute of Paper Science Technology (IPST) has completed third party testing, which demonstrated high yields, good processing attributes, and re-pulpability.

EarthCoating delivers key advantages, including improved barrier and heat seal performance, potential cost savings and a reduced environmental footprint. Various packaging supply chain stakeholders have successfully tested EarthCoating across a broad range of applications, including hot and cold beverage cups, salad and hot bar food trays, frozen food boxes, chilled wine labels (see Ste. Michelle case study) and ice cream packaging. Gold continues, ‘The coating that Smart Planet has created breaks up in the pulper and disappears, and we don’t have the problem of gumming up our equipment. It could be a real boon for our industry.’

Chris Tilton, chief technical officer at Smart Planet Technologies, comments, ‘It’s important to understand the magnitude of the technology. EarthCoating is a real solution for the long-standing challenge of recycling barrier-board and other coated paper materials, including corrugated boxes.’