A new bio-based label adhesive eliminates 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 designed as a direct replacement for petrochemical based adhesives.
The adhesive dissolves completely in PET flake caustic wash recycling operations without clumps or "stickies".
Renewable content of more than 50%
The resin can meet the demands of the PET container recycling streams and offers a renewable content higher than 50%, claim its developers.
It is designed to work on a wide range of plastics, glass and metal containers.
The firm said it would begin manufacturing in the US with concentration on the North American and European markets but would expand distribution worldwide.
Mark K. Jones, vice president of business development at DaniMer Scientific, told FoodProductionDaily.com said lower BOD and the elimination of contamination in recycled flakes is the goal of all plastic recyclers.
When asked what the problems are for recycling labels, Jones 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.”
Jones added the industry has fought the issue as the incumbent adhesive causes yellowing of PET when recycled.
“It eliminates the issue of clumps and stickies in the recycle stream, and has much lower BOD in waste water.
“Unlike traditional adhesives, 92721 can be washed into municipal waste systems,” he said.
The DaniMer adhesive dissolves completely in the PET flake caustic wash recycling operations without clumps in temperatures under 325 degrees.
Jones 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.
“We are always seeking to achieve higher renewable content, and have released a freezer grade #92427 that is 85% renewable.”