Syensqo and TOMRA demonstrate multilayer separation

Syensqo and TOMRA have joined forces to demonstrate the technical and economic feasibility of separating and sorting multi-component plastic structures in which polyvinylidene chloride (PVDC) serves as a barrier layer.

The partners developed a joint set of experiments with multilayer samples of commercial packaging waste consisting of low-density polyethylene (LDPE) and Syensqo’s Ixan PVDC. The results have proven that multilayer films containing PVDC can be separated from mixed plastic waste using industrial sorting equipment to achieve clean-grade polyolefin and PVDC recycling streams.

“The overall target of this project was to challenge major industry standards which claim that multilayer PVDC films cannot be sorted out of multilayer packaging structures,” explained Federico Baruffi, global marketing manager, specialty polymers, at Syensqo.

“Our experiments have demonstrated the contrary and are sending a clear message to the packaging and recycling industry that it can be done, notably with good accuracy and repeatability using existing industrial technology.”

The results apply to markets that are currently generating multi-layer mixed plastic waste containing PVDC, such as shrink films in consumer and food packaging.

“One of the concerns in the recycling industry was the reliable identification of polymeric waste with PVDC content,” adds Marco Gregori, area sales manager Italy at TOMRA Recycling Sorting.

“By combining our advanced optical and near-infrared detection systems, we managed to achieve a selectivity rate of more than 80% when sorting from post-consumer plastic mix and more than 95% when sorting from LDPE monolayer stream. This is yet another example of what today’s technology, in this case our AUTOSORT, can already do.”

Altogether, these results have extended the scope of mixed plastic waste suitable for recycling to a wide range of multi-layer structures containing PVDC.