Catalysing the Conversation: Milliken kicks off a special Ask the Expert Circular Economy Webinar Series

August 26, 2020 by Paul Kearns and Scott R. Trenor, Ph.D.

Milliken’s Lead Sustainability Scientist is the first special guest in a new expert webinar series on the Circular Plastics Economy highlighting where the industry and society need to come together collaboratively to address gaps in the end of life plastics challenge.

As a global manufacturer with long held values of innovation and sustainability, at Milliken, we understand our responsibility to tackle the difficult human and environmental issues that we all face. Our strengthened planet, product and people sustainability goals include reducing our global footprint and creating a more circular plastics economy.

Recently, Milliken’s Lead Sustainability Scientist, Scott Trenor, was able to outline more about our circular economy initiatives as special guest in a new webinar series hosted by the leading magazine Sustainable Plastics. In the first of the Ask the Expert Circular Economy Series, Scott highlighted areas that are ripe for innovation and where the industry needs to work together collaboratively to address technical gaps in the end of life plastics challenge – from packaging design and materials choice to sortation, recycling and reprocessing.

He also outlined Milliken’s initiatives to boost the circularity and sustainability of polypropylene (PP) packaging, including DeltaMax® and Hyperform® HPN® performance additives and our partnership with PureCycle Technologies. These, and work on many other fronts, will be critical in addressing the pollution challenges that have arisen, given that the end of life of plastics is not well managed. This is driving regulatory change and has propelled plastic packaging to the forefront of attention in all aspects of society.

Yet, as Scott outlined, plastic packaging has excellent properties and plays an important role in the safe shelf life extension of fresh fruits and vegetables such as broccoli, mangos and bananas. Fresh proteins such as poultry, beef and fish also benefit greatly. In addition, it has environmental benefits in comparison to other packaging materials, especially when considering climate change.

At Milliken we were honored to kick off the webinar series and hope that the broadcasts serve as a catalyst for research across all fields of polymer science, with the goal of reducing the impact of plastic packaging waste on the environment. Scott received many additional questions following the webinar and we have outlined them, and his responses, here.

How is Milliken approaching recycled content for carpet products?

In line with Milliken’s values, we concentrate product development efforts around ethics, safety and innovation, prioritizing product ingredient optimization and transparency. Milliken evaluates all products with circularity, Life Cycle Impacts, and toxicity (human and environment) as primary considerations. All Milliken product ingredients, including our recycled content, must meet strict market and business requirements. These include compliance for Cradle to Cradle® Certification at a Silver level or above, being “Red List Free” as it relates to the International Living Future Institute’s Declare requirements and meeting strict indoor air quality requirements. Our average modular carpet tile contains an average of 32% recycled content which is included in the yarn and backing systems. Our highest recycled content products contain up to 58% recycled content using the Aquafil Econyl 100% recycled nylon 6 yarn system.

What is Milliken’s approach for closed loop manufacturing of carpets?

Milliken is a founding member of the carpet industry’s Carpet America Recovery Effort (CARE) which is a non-profit committed to finding market-based solutions for carpet recycling in the United States. Milliken is involved with CARE as an active member of the Board of Directors and involved with numerous sub-committees that are focused on the hierarchy of recycling (reduce>reuse>recycle). Milliken carpet products are 100% recyclable. Our broadloom carpet products primarily consist of nylon 6,6 yarns which are the highest recyclable fiber in the industry. Our carpet tiles are the longest lasting product in the industry with a standard polyurethane cushion backing which increases the life of our products by up to 50%. Our landfill diversion program considers reuse of product in secondary applications before recycling. We are active with the latest innovations in global carpet recycling technology. All of our modular carpet products are Cradle to Cradle® Silver certified.

Can DeltaMax® be used in clear or natural applications? Brand owners have made commitments to high PCR content; will enough material be available for this?

The first generation of DeltaMax® cannot be used in natural applications due to the inherent color in the solution. We are launching a second generation that is colorless. As far as clarity, ICPs typically have some haziness to begin with. The DeltaMax solution does not improve this inherent haziness.

Our belief is that without significant system changes, there will not be sufficient PCR material available for brands to meet their commitments. This was recently exemplified by The Recycling Partnership’s “The Bridge To Circularity Putting The New Plastics Economy Into Practice In The U.S.” report. Using rPET as an example, and based on 2017 volumes, they found that to meet a 25% PCR content commitment an additional 1.6 billion pounds of PET bottle would have to be collected. This is equivalent to an additional 100 bottles per person in the U.S. each year and would signify in a 19% jump in the recycling rate for PET.

Why is burning plastic for energy bad? Yes, it is not the optimal solution, but isn't it better than landfilling?

While burning for energy may be a temporary fix and potentially reduce landfilling and mismanagement, we feel that keeping the embedded carbon in circulation for as long as possible is the optimal solution.

Do you have any information of PCR PP in films?

We do not have hard data but there appears to be little PCR PP used in films at this point.

What recycling processes are available for recycling and reprocessing cured silicone components?

There is very little available in this space. We are aware of some grinding and reuse, and Harmony Recycling claims to depolymerize silicones.

Is it possible to have more info about PureCycle, the PP regeneration system, and DeltaMax, and does the presence of DeltaMax m100 in rPP reduce any rPP future re- recycling or could it be considered a way to reach a circular model for the PP?

You can find more information on PureCycle here. For more information on DeltaMax please visit our website. The use of DeltaMax does not affect future recycling and could be part of the solution to reaching circulatory for PP.

You mentioned a series of chemical recycling companies, do you know what some of the byproducts from these processes are and how these companies are having to deal with them?

There is little information publicly available on this. Most of what is reported references between 5 and 15% waste byproduct. What is done with this material is currently unknown to us.

How is Milliken approaching re-using single use plastics that have been contaminated with highly hazardous fluids?

This is particularly important with the current health situation we are all experiencing. We believe that contaminated plastics would be best dealt with advanced recycling streams where the high temperatures would destroy biological contamination.

How are additives helpful in recycling? Also, what should be the maximum/minimum number of additives that can be added without being a problem in recycling?

Additives play an important role in recycling, including normalizing and upgrading processability. For example, our UltraBalance family of products help match shrinkage of PCR PE and PP to virgin resins, allowing molders an option to increase recycled content. As to the number of additives that can be added without being a problem in recycling, this would depend on the additives used and the application. I recommend the APR Design® Guide for Plastics Recyclability and PRE’s RecyClass for information on additives, and the quantities, that could be detrimental to recycling.

Could you please also say a bit about the challenges of recyclability, for example there are many consumer products that cannot be recycled until we make basic changes at design phase.

There are a number of challenges that range from consumers placing items in the recycle bin to sorting to potential contaminates in packaging. Today, we can start to make the shift from complex multi-material packaging to mono-material designs that aid recycling. Our UltraGuard solutions increase the barrier of PE, thus allowing for the removal or reduction of barrier materials and reducing contaminants in the recycling stream.

Do you take into account logistics? If yes, what components are important in that segment of life cycle?

Logistics are important in recycling and reuse models. The APR did consider logistics in its LCA on recycled plastic pellet production. Important aspects include the distance of transportation of recycled material from the home to the MRF and MRF to reclaimer.