Bio-based label adhesive reduces problems with PET container recycling
A new bio-based level adhesive reduces the problems with polyethylene terephthalate (PET) container recycling.
According to its developers, the DaniMer Scientific adhesive combines DuPont Tate & Lyle Bio Products Company’s Susterra propanediol and bio-succinic acid from Myriant.
The patent pending resin, named Danimer 92721, has lower Biological Oxygen Demand (BOD) in waste water and is supposed to be a direct substitute for petrochemical based adhesives.
The adhesive dissolves completely in PET flake caustic wash recycling operations without clumps or “stickies”.
Mark K. Jones, vice president of business development at Danimer Scientific, said that the lower BOD and reducing contamination in recycled flakes is the ultimate target of all plastic recyclers.
He said: “Since there are so many types of labels, and each demands a different recovery system it’s tough to answer, other than our adhesive separates and dissolves so it’s not part of the equation.
“This product answers both the demand for renewable label adhesive in hot melt form, and a clean waste stream for PET recyclers”.
The resin can fulfil demands of the PET container recycling streams and offers a renewable content higher than by a half.
It has been made to work on many materials such as plastics, glass and metal containers.
The firm would begin manufacturing in the US; concentrating on the North American and European markets but expand the work worldwide.
Jones also said the industry battled the problem since the incumbent adhesive causes yellowing of PET when it is recycled.
“It eliminates the issue of clumps and stickies in the recycle stream, and has much lower BOD in waste water,” he said. “Unlike traditional adhesives, 92721 can be washed into municipal waste systems”.
The adhesive disappears completely in the PET flake caustic wash recycling operations under 325 degrees.
He added: “Danimer first patented bio-based hot melts in 2010 for case and carton sealing and is now expanding to the labelling adhesive due to numerous requests from the industry”.