London, England-based Gumdrop Ltd. is the first company in the world to recycle waste chewing gum into a range of new polymers that can be used in the rubber and plastics industry. Having created a program for reclaiming pre- and post-consumer gum for use in material it calls Gum-Tec, the company turned to Teknor Apex to develop and produce compounds from the large waste stream created by the 500,000 ton per year chewing gum industry. The challenge was to devise formulation and manufacturing techniques for an altogether new type of raw material in order to produce commercial-scale quantities of compounds that consistently meet the requirements of specific applications, including optimized elasticity, compression set, tensile properties, and other mechanical properties, as well as processability. According to Gumdrop, the custom compounding expertise of Teknor Apex Company has enabled the advancement of their diversion-from-landfill capability by converting waste gum into a raw material for thermoplastic elastomers (TPEs).
Teknor Apex says they readily accepted the challenge put forward by Gumdrop and applied its expertise as a leading international custom compounder with extensive experience in TPE manufacture. According to Stef Hordijk, senior market manager for Teknor Apex, “We assembled a multi-disciplinary team drawing on our capabilities for materials analysis, process engineering, and manufacturing. The team addressed basic considerations such as feeding it into our equipment, formulating compound recipes using this unique raw material, determining optimal compounding process parameters, and other issues posed by such an unusual feedstock.” Chewing gum waste comprises up to 30% of the new gum-based TPE compounds.
“Like standard TPEs, the Gum-Tec compounds we have developed exhibit a low compression set, can be formulated for either glossy or matte finishes, readily accept colors, and are recyclable,” said Hordijk.
Among the first commercial applications for Gum-Tec compounds was Wellington boots (shown here). Some other applications are shoe soles, caster wheels, automotive bumpers and floor mats, window gaskets, wristwatch straps, toothbrush grips, and extruded pencils.
“Our aim is to divert the substantial amount of chewing gum waste and convert it into Gum-Tec compounds for use in the runner and plastics market, giving this waste stream a second life and putting it to use in high-quality end products that contribute to sustainability,” said Anna Bullus, director at Gumdrop Ltd. “Every kilogram of chewing gum that goes into a Gum-Tec compound means one less kilogram going to the landfill.”
