天美传媒

MURRAY, Ky. 鈥� Dr. Kevin Miller, professor and chair of the Department of Chemistry at 天美传媒 University, partnered with researchers at the University of Minnesota to develop technology for new multi-block copolymer compatibilizers that improve the recyclability of mixed plastic waste streams.

The technology specifically targets streams that contain mixtures of polyesters such as polyethylene terephthalate (PET) and polyolefins such as polyethylene (PE), two of the most utilized commodity plastics, which together constitute 40-50% of all plastic waste globally.

Recycling of plastics in the U.S. remains at a surprisingly low level (less than 9%, according to a 2020 research article that Miller also contributed to, which can be found at ) with most plastic waste ending up in landfills or being incinerated; therefore there is a great deal of interest in exploring relatively inexpensive alternatives to current recycling technologies.

Polyolefins and polyesters such as PE and PET are commonly used in packaging, especially for food, in the form of films made up of layers of different types of plastics adhered together. These films are rarely recycled as the layers are extremely difficult to separate physically, and traditional melt reprocessing is not effective because liquefied PET and PE do not mix, resulting in reprocessed films which lack the necessary mechanical properties for reuse.

The new patented technology describes a process by which multi-block copolymers are used at low levels during melt processing to essentially 鈥渢ie鈥� the layers together like a piece of thread. The reprocessed films were found to exhibit stronger polyester/polyolefin interlayer adhesion than the original multi-layered material as demonstrated through the analysis of mechanical properties and scanning electron microscopy images taken after freeze-fracturing.

Overall, the technology represents a significant advancement in the recycling or upcycling of PET/PE waste streams through the melt blending of preformed multi-block compatibilizers. The technology could be applied to PET/PE mixed-plastic waste streams which are either impossible to physically separate through traditional melt reprocessing or too inconvenient to sort. Further, products where the multi-block compatibilizer is preloaded into the virgin material could make them ready for recycling after their initial use.

Support for the research was provided by the National Science Foundation-sponsored Center for Sustainable Polymers at the University of Minnesota, and was completed in collaboration with Dr. Christopher Ellison, professor of chemical engineering and materials science at the University of Minnesota.

The patent (US 12281204 B2) was issued in April of 2025.

鈥淚鈥檝e known Chris Ellison since our days as senior scientists at the Rohm and Haas Company in the mid-2000s,鈥� said Miller. 鈥淓ven then, Chris was an excellent visionary. We鈥檝e collaborated several times since moving to academia, but this project in particular was the first time where we dove head-first into an area of serious global concern. Plastic pollution is a major problem, and scientists must develop creative and relatively inexpensive ways to recycle or upcycle commodity 鈥榯hrow away鈥� plastics. Chris had an idea that these multi-block compatibilizers might help with recycling PET/PE mixed plastic waste, and he needed someone with synthetic expertise. That鈥檚 where our team at 天美传媒 fit in. We developed the technology to tie the PET and PE linkers together and support the overall intellectual discovery.鈥�

The PET polymers, as well as the multi-block copolymers, were prepared and characterized at 天美传媒, while the PE polymers, film fabrication and film testing were completed at the University of Minnesota.