Earlier this year, I proposed to form an internal working group at PLASTICS to review a wide variety of literature on plastics research and create a catalog of objective and positive plastics research in response to the onslaught of biased criticisms against a material that has made tremendous positive contributions to society.
By Perc Pineda, Ph.D.
Chief Economist
Earlier this year, I proposed to form an internal working group at PLASTICS to review a wide variety of literature on plastics research. The group is composed of PLASTICS staff—Andy Brewer, Madeline Kramer, and Brennan Nesvacil, and yours truly. We came across studies that incentivized plastics recycling in Spain, engaging citizens in active collection using an app.[1] There’s also a study that showed no reduction in pollution levels through extended producer responsibility in Canada.[2] Another study on countries that are in the thick of the marine litter issue articulated proactive solutions to solid waste management.
Using technical and social approaches, the study found that solid waste management was country-specific, and decentralization is the most appropriate management approach. This was the finding of Dholhikah and Trihadiningrum (2012) in “Solid Waste Management in Asian Developing Countries: Challenges and Opportunities”.[3] The authors, who have first-hand experience in solid waste management in the region, did not recommend product bans.
There is a push to recycle more materials, not just plastics. After all, this is a multi-material economy. This simply means that to achieve sustainable levels of global economic growth, materials need to be used for their best applications. During our research, however, we also found studies that raised questions on the environmental impacts of other materials.
For instance, Pivenko, Eriksson, and Astrup (2015) in “Waste paper for recycling: Overview and identification of potentially critical substances” argued that lower quality paper may potentially lead to accumulation or unintended spreading of chemical substances contained in paper.[4] According to the authors, “the study clearly demonstrates that there is a need for more comprehensive quantitative data documenting the levels of potentially hazard substances in paper sent to recycling as well as the final paper products. Based on hazard screening procedure, 51 substances have been identified as potentially critical. It is recommended that analytical efforts are directed towards these substances.”
Brennan Nesvacil
How effective is recycling? On plastics, is there a difference between recycled and virgin material? These are valid questions to ask in today’s age of technical information and awareness but there is only one true response: it’s complicated. That’s what Brennan Nesvacil, Manager of Global Packaging Regulations and Processors of PLASTICS found.
The most common form of recycling is mechanical. Mechanical recycling takes a variety of materials and uses simple and inexpensive processes to form its recycled counterpart. The main advantages of mechanical recycling, apart from being cheaper than other forms of recycling, are the ability to be decentralized and having low technical requirements. However, the quality of the recycled material is entirely dependent on the quality of the input stream, which leaves room for improvement when the material can get rejected both before and after the recycling process due to qualitative requirements. As Nesvacil found in Shamsuyeva and Enders (2021) study “Plastics in the context of the circular economy and sustainable plastics recycling: Comprehensive review on research development, standardization, and market” the development of a Circular Economy Model for plastics products requires close cooperation of scientists with standards committees and industry.[5]
But to Nesvacil, there is another player in the game, one that may hold more promise than we think: chemical recycling. This form of recycling, though still in its early stages of technical understanding and implementation, is nearly independent of the quality of the input stream and can boost recycling rates that are significantly higher than mechanical with more quality output. The idea is to depolymerize plastic materials under controlled conditions and use the recovered chemical constituents as feedstock for new materials. The only downfall to chemical recycling is the cost but, as more methods and applications come to be, the advantages will undeniably outweigh any reason not to use it.
So what does that mean for us now? Mechanical recycling is dominantly used but if you ask that question again in five years, the answer may be entirely different.
We also found studies in line with PLASTICS’ New End Market Opportunities initiative (NEMO).
Andy Brewer
Another member of the research working group, Andy Brewer, Association Director, Sustainability and Materials at PLASTICS, found a recent study published in 2020 proved how recycled plastic bottle strips can be used to strengthen structural columns in building construction. The study, by Ongpeng, et al “Strengthening rectangular columns using recycled PET bottle strips” used twenty-seven identical concrete columns that were 12” tall, making nine sample designs with three specimens each.[6] Recycled polyethylene terephthalate (RPET) bottles were cut into strips and placed around the sample columns. The sample designs differed with RPET strip spacing, ranging from 5mm to 25mm. The strips were long enough to reach around the full width of the column and then were bound to the column using a small piece of sheet metal acting as a clamp.
Once the samples were prepared, testing was completed using a uniaxial compression machine, and stress and strain measurements were recorded using a strain gauge. The results of this simple study were shocking. Results showed that a few of the column samples with the confined RPET strips provided a significant increase in axial strain and compressive strength. A 70% increase compared to low-strength concrete regularly used in construction.
The study proved that there was a potential pathway for using recycled PET bottles as a strengthening material in concrete and also a great way to contribute to managing plastic waste.
With his background in global manufacturing systems and engineering technology, Andy appreciates this research: “It was simple, effective, and a solution to plastic recycling that could potentially keep others out of harm and danger. It shows that you do not need to try and re-invent the wheel when it comes to recycling plastics. The use of plastics in our daily lives is here to stay and solutions are everywhere you look.”
A second study Andy found covered research on turning recycled low-density polyethylene (LDPE) into an advanced biomedical product. The biomedical product is a noninvasive glucose sensor used for patients with diabetes. The study by Lanzalaco, et al (2020) used LDPE in the form of food packaging that was treated with atmosphere corona discharge plasma for electrochemical detection. [7] The sensors manufactured using the recycled LDPE act as a mediator capable of communicating with the glucose enzyme. This makes the device able to detect glucose concentrations in both healthy and diabetic patients’ sweat. Two samples were used, recycled LDPE with additives, and recycled LDPE without additives. After testing it was found that the LDPE does not require a pre-treatment to eliminate additives. Biomedical sensors with recycled LDPE can play a crucial role in monitoring diabetes in countries with underdeveloped medical fields.
Madeline Kramer
We also looked at studies by foreign governments. For instance, Madeline Kramer, Associate of the Equipment Council, reviewed “A Circular Economy for Plastics – Insights from research and innovation to inform policy and funding decisions by the European Commission (2019). [8]Based on the research on plastics pollution and recycling, actual policy recommendation and examples of business models to help create a better and more sustainable industry were presented. The goal is to set up, connect and fund mechanisms to coordinate the transition towards a circular economy and to invest in upstream and downstream capacity across Europe while also providing funding for research and creating financial incentives for innovation in business models, products, and materials fit for a circular economy for plastics. As Madeline put it, “I believe this research and insight is very important and relevant to the industry and the work that PLASTICS is doing today because they recognize the importance of and value that plastics brings while also pointing out where the industry can improve and grow.”
In contrast to the U.S. policy, the underlying objective of some interest groups and other materials industries is to ban plastic and plastic products. It has been easier to propose legislation to either ban or tax plastics. However, recognizing that updating U.S. recycling infrastructure—which would benefit all types of materials since it is a multi-material economy—has been difficult for legislators to do and act upon.
The work of the research working group ends in December. By then a catalog of positive research on plastics will be available to PLASTICS members, nonmembers, and the media. The goal is to arm the industry with objective and positive research on plastics to be able to respond to the onslaught of biased criticisms against a material that has, over the years, made tremendous positive contributions to society.
[1] Reference study “Incentives for plastic recycling: How to engage citizens in active collection. Empirical evidence from Spain by Gibovic and Bikfalvi, Apr. 2021 (Recycling)
[2] Lucas Harris, Max Liboiron, Louis Charron, Charles Mather. (2021). Using citizen science to evaluate extended producer responsibility policy to reduce marine plastic debris shows no reduction in pollution levels, Marine Policy, Volume 123, 2021, 104319, ISSN 0308-597X, https://doi.org/10.1016/j.marpol.2020.104319.
[3] Dhokhikah, Yeny & Trihadiningrum, Yulinah. (2012). Solid waste management in Asian developing countries: Challenges and opportunities. J. Appl. Environ. Biol. Sci.. 2. 329-335.
[4] Pivnenko, K., Eriksson, E., & Astrup, T. F. (2015). Waste paper for recycling: Overview and identification of potentially critical substances. Waste Management, 45, 134-142. DOI: 10.1016/j.wasman.2015.02.028
[5] Madina Shamsuyeva, Hans-Josef Endres. (2021). Plastics in the context of the circular economy and sustainable plastics recycling: Comprehensive review on research development, standardization and market, Composites Part C: Open Access, Volume 6, 2021, 100168, ISSN 2666-6820, https://doi.org/10.1016/j.jcomc.2021.100168.
[6]Ongpeng, Jason & Aviso, Kathleen & Tan, Raymond. (2020). Strengthening rectangular columns using recycled PET bottle strips. Engineering Science and Technology an International Journal. 24. 10.1016/j.jestch.2020.07.006.
[7] Sonia Lanzalaco, Georgina Fabregat, Helena Muñoz-Galan, Jordi Cabrera, Xavier Muñoz-Pascual, Jordi Llorca, and Carlos Alemán ACS Sustainable Chemistry & Engineering 2020 8 (33), 12554-12560. DOI: 10.1021/acssuschemeng.0c03545.
[8]Hannah Ritchie and Max Roser (2018) – “Plastic Pollution”. Published online at OurWorldInData.org. Retrieved from: ‘https://ourworldindata.org/plastic-pollution’ [Online Resource].
