Materials Science

In pursuit of sustainable plastics

By Yuliya Streen, Global Strategic Marketing Manager – Polymers at Kraton Corporation

Yuliya Streen, Global Strategic Marketing Manager – Polymers at Kraton Corporation, outlines a holistic approach to managing a p

Yuliya Streen, Global Strategic Marketing Manager – Polymers at Kraton Corporation, outlines a holistic approach to managing a product’s life cycle that is key to addressing plastic waste.
Since 2018, the plastic industry has been rapidly shifting towards holistic sustainability, which encompasses the entire product life cycle across the value chain in a transparent way. This can include the use of biobased, circular feedstock; generating fuel from plastic waste pyrolysis; developing recyclable and reusable end product design; or increasing recyclate content. The broader societal awareness and growing consumer concerns about plastic pollutions’ devastating impact drove industry players and government to take public action. Some large brand owners have made pledges to improve recyclability, reusability and recycled content in their consumer products.

It is important to remember that plastics itself is not the problem. Rather, it is how the material is used, from its inception to the end of life. The plastic product life cycle starts from choosing the resin and product design, followed by manufacturing and marketing, purchase and consumption by end consumer, and then reuse and recycling at the end of life (Figure 1, courtesy of Kraton Corporation). To drive change successfully as a society, structural barriers must be removed to enable scalable success. This includes addressing consumer choice, recycling infrastructure, unfavorable economics, safety and regulations, and product performance.
Factors to success
Consumers are increasingly taking responsibility for how they choose, buy, use, reuse and recycle their products. Part of the consumer responsibility is taking the time to understand challenges to manufacture products in a sustainable way, and there is a willingness to potentially pay more for sustainably manufactured products and accept necessary changes in the product packaging design. Consumer learning and their commitment to recycling products the right way also aids in the reusability of residential recycling waste streams.
Effective collection and sorting infrastructure are a critical element to bringing the product’s end-of-life back into the circular economy. The existing infrastructure is a limiting factor in ensuring sufficient amount of post-consumer recycled plastics availability for future reuse. To enhance collection volume, the curbside recycling programs and material recovery facility (MRF) centers require multi-level funding and support. The recent introduction of the Realizing the Economic Opportunities and Values of Expanding Recycling (RECOVER) Act1 advocates for targeted funding to improve recycling infrastructure and education in the US. Furthermore, the ability to automate sorting of recycled waste streams will increase reusability, allowing for upcycling and improving the economics for the recycling centers.
In many cases, it is not the material cost itself but the extra processing steps and process yield loss that make post-consumer resins (PCR) costly compared to virgin materials. To bridge these unfavorable economics, countries such as the UK consider incentivizing recycled plastic use through premium taxation laws on virgin plastics.2 Government mandate on the recycled plastics content is another way to drive change. The recently vetoed California legislation requiring 50% recycled content PET bottles would have been an example of the most stringent regulatory enforcement worldwide.3 Undergoing value chain integration and consolidation with the purchase of recyclers by the large virgin resin producers can help improve the financial viability of reusing PCR with better scalability and position to capture value. Chemical recycling is another economic alternative to manage otherwise unusable PCR. That is why there are so many investments and partnerships around building chemical recycling facilities globally.
Ensuring product safety throughout its life and reuse is also essential for long-term sustainability. To achieve this, there is a need for common industry practices and updated regulations that provide guidance and clarity on the reuse of recycling waste streams across different applications.
Finally, multi-resin compatibilization and product performance are essential factors. PCR’s ability to consistently meet performance and color specifications still poses a challenge for manufacturers. The optimal objective is to incorporate the recycled content without compromising the product’s mechanical properties, weight or branded color and achieve effective compatibilization of mixed streams. Products such as Kraton styrenic block copolymers can help enable compatibilization of different materials to produce a high-quality product, even after repeated recycling (see Figure 1 for reference). These polymers – which are fully recyclable – can improve properties such as impact resistance while enabling increase of the percentage of recycled content to reduce the use of virgin material.
A collective effort
Advancing recyclability to solve the plastic waste problem is a complex, multi-faceted challenge. Therefore, it is critical to continue expanding collaboration and information sharing across the value chain – from material suppliers to government and industry associations to consumers. Enhanced end-to-end transparency and joint learning will promote the reapplication of best practices and accelerate developments that solve technical challenges easing the overall sustainability journey. Kraton is expanding its collaboration across the value chain to develop innovative sustainable solutions for consumer use. As the global society continues to pursue options to address plastic waste, raw material suppliers such as Kraton will increasingly play a key role in that collective effort by offering a holistic product life cycle approach with versatile sustainable solutions that enable the circular economy.
Yuliya Streen, Global Strategic Marketing Manager – Polymers, Kraton Corporation