Courtesy of Nova Chemicals
This article appeared in the January 2025 issue of Resource Recycling. Subscribe today for access to all print content.
Designing packaging for recyclability is an important part of building a circular economy. For plastics, structures that are designed with consideration for existing recycling methods can contribute to higher-
quality recyclate and help strengthen the supply of post-consumer recycled material in the future. Although it involves a thorough understanding of downstream collection and recycling processes, designing for recyclability really begins with upstream producers.
Beyond performance and aesthetics, examining packaging from a recycler’s point of view involves considering how the package could be collected, sorted and processed. Because mechanical recycling is the most widely available recycling method today, many companies are moving toward mono-material packaging designs that could enable higher-yield PCR feedstock bales in the future. However, mono-material structures must be able to meet the necessary barrier and sealing requirements of incumbent structures to be a viable alternative to mixed-material laminates and films. Balancing these performance requirements, equipment capabilities and consumer expectations of how the package should function can prove quite difficult for brand owners.
How can the packaging industry advance technology innovations that fulfill all of these specifications? Through their studies exploring how to build a circular economy, the Ellen MacArthur Foundation has identified external input and breaking down silos as two key ingredients for a successful upstream innovation process. Brand owners know the type of product and experience they want to deliver to consumers. Suppliers understand the capabilities and limitations of different materials. Bringing various areas of expertise together through cross-value-chain collaboration streamlines and accelerates the commercialization of packaging solutions that deliver the desired experience for consumers while considering the post-use cycle of the product.
The growing availability of high-density biaxially oriented polyethylene is one example that illustrates how resin suppliers, film manufacturers and original equipment manufacturers worked together to bring a new PE material to market that enables new types of mono-material packaging. Working with biaxial film manufacturers like Inteplast, Nova Chemicals expanded BOPE-HD availability and capacity by running trials and collaborating closely with the experts in biaxial film production. These relationships helped refine the BOPE-HD formulation to meet converter and brand owner requirements. “Every step of the value chain has to work together in order to make sure that we end up with a product that meets the needs of the market,” said Latricia Fry, market and business development manager at Inteplast.
Market demands
The development of BOPE-HD began with an increased interest in mono-material PE solutions from brand owners. Motivated by NGOs like the Ellen MacArthur Foundation, emerging extended producer responsibility legislation and consumer preferences, many companies have made sustainability commitments related to making packaging recyclable and incorporating PCR materials.
PE is suitable for a wide variety of packaging applications due to its moisture barrier properties. While HDPE has established recycling streams and is one of the most recycled types of plastics, the majority of flexible packaging films end up as waste. Store drop-off programs are currently the only consumer recycling program for plastic films on a large scale, and they only accept a portion of PE flexible packaging. GreenBlue, the organization behind the How2Recycle labeling system, reports that only 36% of program members’ flexible packaging qualifies for store drop-off recycling, while the remaining 64% is not yet accepted.
In light of its versatility and its developing options for recycling, PE is a common choice for mono-material packaging designs. When Inteplast began exploring BOPE, they started with linear low-density
PE but discovered that it could not meet all of their customers’ needs. The goal of designing mono-material structures is to replace multi-material PET and PE laminates. These materials demonstrate high stiffness and heat resistance, and LLDPE could not meet the same types of processing requirements. The market was demanding an HDPE solution.
Product development
Nova Chemicals started down a new path altogether when they began developing their BOPE-HD resin for tenter frame lines, as the process requires a different formula than blown PE film. To create the resin that could run on commercial tenter frame lines, including lines designed for biaxially oriented polypropylene, they had to create a completely new formula that would not slow down or limit production. As all operators work on maximizing line speed, maintaining productivity for the new HDPE material was essential, though working with HDPE in this process is technically challenging. To develop a functional resin that could be widely adopted, Nova formed strategic relationships with film manufacturers.
Nova and Inteplast embarked on a journey to test resin formulations and production processes for the BOPE-HD resin. The Nova team conducted trials on Inteplast’s tenter frame lines. Nova and Inteplast team members attended OEM demonstrations together to better understand how the resins could run on existing and new equipment. At Nova’s Centre for Performance Applications in Calgary, Inteplast and other brand owners tested films on converting equipment and shared feedback to improve the functionality of the resin.
Benefits of collaboration
Developing a new product requires lots of testing and many different iterations. The exchange of information and an open dialogue between multiple industry players throughout the process aligns everyone’s objectives, helping teams pursue the right research and modifications. “Any time a packaging design changes, there will never be a drop-in solution that solves everyone’s problems,” Fry explained. “Adjustments will always need to be made, and sharing feedback during the development stage ensures that we are all following the right path and narrowing in on our process.”
For mono-material structures, new films need to work within existing production capabilities to be competitive and profitable. Collaboration enables new developments that account for the manufacturing, processing and performance needs throughout the entire packaging value chain. “Collaboration really is the only way we’re going to be able to solve the demand for circularity when it comes to flexible films,” said Fry.
The industry must focus on creating accessible mono-material packaging solutions that provide an alternative to non-recyclable, mixed-material films. As the world comes together to increase plastic recycling and reduce plastic waste, it is important to start these system-level changes with existing opportunities like packaging designed for store drop-off programs and optimized for mechanical recycling processes. Downstream solutions alone will not be able to tackle plastic without upstream innovation supported by diverse teams and collaborative thinking.
Brant Wunderlich has extensive experience in the packaging industry and is currently the team leader for application development and circular economy at Nova Chemicals, a leading producer of polyethylene resin that strives to solve industry challenges and circular solutions for our customers and organizations across the value chain.
The views and opinions expressed are those of the author and do not imply endorsement by Resource Recycling, Inc. If you have a subject you wish to cover in an op-ed, please send a short proposal to [email protected] for consideration.