Advocating for the use of PCR in plastic aerosol containers

Written on: December 1, 2023 by Nicholas Georges

By Nicholas Georges, HCPA Senior VP, Scientific & International Affairs with the HCPA Aerosol Products Division Plastic Aerosol PCR Task Force i

Sustainability has become an integral part of every business and companies have been exploring opportunities to improve their environmental footprint. This includes reducing energy use, decreasing emissions from transportation and redesigning primary, secondary and tertiary packaging.

Increasing the use of post-consumer recycled (PCR) content—through both voluntary initiatives and compliance with State mandates—is one way that companies are reducing the environmental impact of a product’s packaging.

Companies in the household and commercial products industry should be aware of current rules in New Jerseyii and Washington Stateiii that set minimum PCR content requirements for rigid plastic packaging and household cleaning and personal care products in plastic packaging, respectively. However, some Federal requirements prevent packaging from containing PCR. Then what?

That’s the exact issue for aerosol manufacturers and marketers that want to use plastic aerosol containers in the U.S. The Pipeline & Hazardous Materials Safety Administration’s (PHMSA) requirements for plastic aerosol containers do not allow for the use of PCR, per 49 CFR 178.33b-6 (bolding added for emphasis):

Each container must be manufactured by thermoplastic processes that will assure uniformity of the completed container. No used material other than production residues or regrind from the manufacturing process may be used. The packaging must be adequately resistant to aging and to degradation caused either by the substance contained or by ultraviolet radiation.

A Federal regulation should pre-empt State requirements; however, it’s always possible for a State to decide differently, which requires litigation to make the ultimate decision. Rather than spending significant time and resources going through the court system, members of the Plastic Aerosol Research Group, LLC (PARG)iv used both analytical and physical property test measurements to analyze the impact of container integrity with various levels of PCR, specifically Solid-Stated Polymerization (SSP) Polyethylene Terephthalate (PET), compared to plastic aerosol containers that used only virgin PET.

The analytical tests consisted of Intrinsic Viscosity (IV) and Differential Scanning Calorimetry (DSC), which indicate the strength, thermal stability and integrity of the material and can predict anomalies and degradation in the polymer.

Through these studies, PARG looked at the base resins, as well as the pre-forms made with resin variables of 100% virgin (no PCR), 25% PCR, 50% PCR, 75% PCR and 100% PCR (no virgin material). The results showed no significant differences between the virgin and PCR resin blends.

The physical property tests included the burst strength, drop impact and resistance to temperature conditions. The data demonstrated that adding solid-stated polymerization PCR to virgin PET can produce a container that is of equal quality to a virgin PET container. That being said, manufacturers and marketers must still perform testing to assure stability and performance of the container once a formulation has been added.

Based on the results of these tests, combined with previous researchv that showed UV exposure is not expected to cause any significant difference in the performance properties of virgin and recycled PET with similar intrinsic viscosities, PARG members were able to conclude that there is no significant difference in the physical integrity of plastic aerosol containers containing only virgin PET or various levels of SSP PCR.

While PARG completed its overall mission and has since dissolved, the Household & Commercial Products Association’s (HCPA) Aerosol Products Division has published this work in a white paper, available here. HCPA and members of the aerosol industry will use this work to educate PHMSA in the hope that it will modify its regulation and allow the use of SSP PCR.

For more information on this work or to get involved with this advocacy, please contact Nicholas Georges at SPRAY

i Andy Franckhauser, P&G; Priyan Manjeshwar, Plastipak; Rodney Prater, SC Johnson; Scott Smith, Plastipak
ii S 2515
iii SB 5022
iv The Plastic Aerosol Research Group, LLC (PARG) was an internationally recognized consortium involved in the global advancement of the aerosol industry. The PARG charter was to grow the industry through good science and innovative processes. PARG was an advocate of the expansion of the aerosol container platform in an effort to grow the aerosol industry as a whole.
v Study of UV Degradation on Plastic (PET) Aerosols, Rochester Institute of Technology (RIT), Journal of Applied Packaging Research (full study available here)