Avient and Borealis announced the results of a new joint study for the K 2022 Trade Fair. The study addresses the challenges of color matching in PCR for rigid packaging, offering options that can create global color consistency, quality, and circularity.
In 2018, Borealis launched EverMinds™, an umbrella platform uniting its activities and initiatives aimed at advancing action on circularity. Bridging from the EverMinds™ platform, Borealis and Avient recently completed a joint application study investigating how to optimize color matching when using post-consumer recycled material (PCR) in rigid packaging applications. Insights obtained from the joint study will help value chain partners and customers take advantage of the wide range of color options that can be enabled by the use of Borcycle™ M compounds (mechanically recycled polyolefins) from Borealis and color solutions from Avient for even the most sophisticated application requirements.
Why Avient and Borealis undertook this study
In order to enhance the sustainability of rigid packaging, the industry is seeking ways to incorporate higher amounts of PCR into its products without compromising on functionality or shelf appeal. Keeping in mind that color is a key element of a pleasing appearance, the recyclate’s intrinsic color-matching properties are more limited compared to virgin polymers. In addition, the market availability of PCR in light and natural tones is equally limited. Moreover, coloring processes for dark recycled material can be challenging due to the need for high amounts of colorant to overcome the PCR base color.
Key takeaways from the research
The joint study demonstrated that using certain components together from both companies can more consistently produce a wide range of color options for PCR material without having to add high levels of colorant. Those components include Borcycle M 100% recycled polypropylene (rPP) from Borealis in tandem with colorant formulations from Avient along with Avient’s PCR Color Prediction Service, which could digitally illustrate the colorant formulations that are possible. Plus, the color formulations have been specifically developed for use with PCR without disturbing detectability in the sorting process.
Another key discovery from the study: If colorant must be added to the base material to achieve the desired color, the addition of color concentrate can be low (around 2%). The higher translucency of Borcycle M compounds is one facilitating factor in better color matching, thanks to the materials’ good light transmission and color absorption. The study also demonstrated that using Borcycle M grades along with Avient’s OnColor™ near-infrared (NIR) detectable colorants can produce a recyclable, neutral black which enables better automatic sorting for recycling. This solution helps to prevent downcycling of darker and black PCRs based on their color and maintains their value in the recycling stream.