Document 4aaj5wYgvyMDx3kG6BmK4rLnV

2225 W. Chandler Blvd | Chandler, AZ USA White Paper for EU Annex XV Restriction Report and under REACH Rebecca Agapov, Ph.D., Scott Eastman, Ph.D., William F. Scholz, Ph.D., Peter Walsh, Ph.D. I. Scope: Exclude Fluoropolymers from the Proposed Restrictions on PFASs The current Annex XV Restriction Report ("Annex XV Report") proposes to restrict "any substance that contains at least one fully fluorinated methyl (CF3-) or methylene (-CF2-)" (Agency, 2023). This definition is used due to concern with safety profiles of these per- and polyfluoroalkyl substances ("PFASs"). Specifically, that they are, or ultimately transform into, persistent substances; are soluble and mobile in water and thereby able to contaminate surfaces, ground- and drinking water or soil; and are toxic and/or bio accumulative, both with respect to human health as well as the environment (Agency, 2023). This definition of PFASs communicates that the compounds under this term share the same structural trait of having a fully fluorinated methyl or methylene moiety. However, it does not inform whether a compound presents risk or not. In this broad definition, there are distinct substances with very different properties: polymers and non-polymers; solids, liquids, and gases; persistent and nonpersistent substances; highly reactive and inert substances; mobile and insoluble; eco-toxic and nontoxic chemicals. In addition, this definition covers a broad range of molecular structures- neutral, anionic, cationic, aromatic, low or high molecular weight- and therefore diverse physical, chemical, and biological properties. It is for all these reasons that the definition of PFASs is too broad, as written, and the chemicals it covers should be considered in separate groups for risk assessment and management. One unique category that should be separated out for risk assessment and management is fluoropolymers. Fluoropolymers are a class of materials with high molecular weight. Examples of fluoropolymers are: polytetrafluoroethylene ("PTFE") CAS # 9002-8-0 (CF2CF2)n; perfluoroalkoxy alkane ("PFA") CAS # 26655-00-5 (CF2CF2)n-(CF2CF(OCF3))m,; fluorinated ethylene propylene ("FEP") CAS # 25067-11-2 (CF2CF2)n-(CF2CF(CF3))m; and ethylenetertafluoroethylene ("ETFE") CAS # 25038-71-5 (CF2CF2 CH2CH2)n. Fluoropolymers have unique properties that are a result of their very high molecular weight, generally over 100 kg/mol. Each repeating unit of a fluoropolymer has an extremely strong carbon-fluorine (C-F) bond, in fact the strongest bond that can exist between C and another atom, making them highly stable materials over a very wide temperature range (Olabisi & Adewale). In addition to the thermal stability, fluoropolymers also have high chemical, oxidative, hydrolytic, and biological stability. PTFE is inert inside the body, without degradation, and is commonly used in heart stents and hernia meshes (nek, et al., 2019). The size of the molecule makes it impossible for the fluoropolymers to cross cell membranes. In addition, fluoropolymers are inherently non-flammable, and are highly resistant to degradation. The polymeric materials have negligible residual monomer and/or oligomer content, and low to no leachable materials (Gangal & Brothers), making the risk of ground water contamination negligible. As a result, fluoropolymers do not present significant toxicity concerns and cannot degrade into other PFASs. 1 2225 W. Chandler Blvd | Chandler, AZ USA It has been widely recognized that certain chemical properties, specifically molecular weight, limit the ability of a chemical to cross the cell membrane and therefore limit its bioavailability. Examination over time has resulted in a collection of data to relate the chemical properties and structure of a given chemical to its hazard potential. These factors support the "polymers of low concern" ("PLC") criteria as defined by the Organization for Economic Cooperation and Development ("OECD") (Development, 1993 Apr), which have been accepted by Australia, Canada, China, Japan, Southern Korea, Philippines, New Zealand, Taiwan, and the United States (Deloitte, 2015). The PLC criteria are further detailed in the references cited here, (Development, 1993 Apr) (Deloitte, 2015), but include molecular weight, ionic character, reactivity, and residual monomer content, to name a few. Fluoropolymers satisfy the PLC criteria and are as such considered to be "low concern" to human health and the environment (Henry, et al., 2018). The physical-chemical properties of fluoropolymers prevent bioavailability, bioaccumulation, toxicity, and degradation. Fluoropolymers are also not water soluble, and not subject to long-range transport. Due to the large size of these molecules, fluoropolymers cannot cross the cell membrane (Henry, et al., 2018). Based on review and assessment of fluoropolymer toxicity data, human clinical data, and physical, chemical, thermal, and biological data, research has concluded that fluoropolymers are distinctly different from other nonpolymeric PFASs (Korzeniowski, 2023). Grouping fluoropolymers together with all classes of PFASs for a single approach to structure-hazard assessment based on persistence alone is therefore not scientifically appropriate. For this reason, we strongly believe that a distinction must be made within the definition of PFASs included in the PFASs Proposal, and that the following fluoropolymers should be excluded from the proposed restrictions: I. polytetrafluoroethylene ("PTFE") CAS # 9002-8-0 (CF2CF2)n; II. perfluoroalkoxy alkane ("PFA") CAS # 26655-00-5 (CF2CF2)n-(CF2CF(OCF3))m; III. fluorinated ethylene propylene ("FEP") CAS # 25067-11-2 (CF2CF2)n- (CF2CF(CF3))m; and IV. Ethylene tetraflouroethylene ("ETFE") CAS # 25038-71-5 (CF2CF2 CH2CH2)n. This distinction is scientifically supported as large molecule fluoropolymers have been demonstrated to be safe and do not pose significant risk to human health (Korzeniowski, 2023). II. Specific Uses of PFASs: Request for a Temporary Exemption for the Use of Specific Fluoropolymer PFASs in Aerospace & Defense Wire and Cable Applications There are several wire & cable components in the aerospace and defense sectors that utilize PFASs. Polytetrafluoroethylene ("PTFE"), perfluoroalkoxy alkane ("PFA"), Ethylene tetrafluoroethyene ("ETFE"), fluorinated ethylene propylene ("FEP"), and fluorinated polymeric hydrophobic and oleophobic coatings are used in the manufacture of electrical insulation for power distribution, 2 2225 W. Chandler Blvd | Chandler, AZ USA high signal integrity wire & cable, and cable terminations. Since PTFE materials are expensive to purchase and fabricate, they are only used when their performance attributes are absolutely essential. The aerospace & defense wire and cable applications that utilize fluoropolymer-based materials are critical to ensure our current standard of aerospace safety and to supply defense assets needed to maintain geopolitical stability in Europe and across the globe. These flight-critical applications require superior electrical performance and exceptional stability and reliability to operate in the aerospace service environment. There are no other alternative materials that have demonstrated consistently robust electrical performance during high altitude, low atmospheric pressure conditions, high temperature excursions, while demonstrating long service lifetimes of approximately 20 years. Key Functionalities Provided by PFASs: Aerospace & Defense - Wire and Cable Components The Annex XV Report acknowledges that PFASs are commonly used in the production process of aerospace wire and cable components. It should be emphasized that specific fluoropolymers (PTFE, PFA, ETFE, and FEP), and fluorinated polymeric hydrophobic coatings are the primary materials constituting the internal layers of the cable as well as the materials used in termination of the cable (referred to herein as "cable terminations"). As such, these specific fluoropolymers are the key enabling constituents of the performance required of such wire and cable components and terminations for mission-critical applications due to their unique combination of properties: I. Low dielectric constant and low dissipation factor enabling superior performance as wire & cable insulation. II. High dielectric strength enabling superior performance as wire & cable insulation. III. High resistance to failure by partial discharge and corona discharge enabling superior performance as wire & cable insulation. IV. Hydrophobic surface of about 18-20 mJ/m2 increases resistance to failure by surface tracking enabling superior performance as an electrical insulator at cable terminations. V. Stable over varying environmental conditions such as high altitude/low atmospheric pressure, high humidity, and temperatures from -55C to 260C, enabling stable performance during environmental excursions. VI. Inherently flame retardant, eliminates need to include halogens and other fireretardant additives of high environmental risk. As explained further below, PTFE, PFA, FEP, and ETFE are used in multiple aerospace applications such as power distribution systems, high signal integrity cable, and cable terminations. Fluoropolymer Use Application: Aerospace Power Distribution Wire and Cable, High Signal Integrity Cable, Cable Termination Aerospace electrical insulation has been identified by NASA as a core technology required to guarantee safe operation of commercial aircraft (NASA, 2011). The crash of Trans World Airlines 3 2225 W. Chandler Blvd | Chandler, AZ USA Flight 800, a Boeing 747-100 aircraft, in the Atlantic Ocean East of Long Island, USA is instructive (Board, 1996). The investigation conducted by the National Transportation Safety Board ("NTSB") determined the crash was caused by an electrical insulation failure leading to a short circuit and detonation of a fuel tank. Similar safety considerations are in play in defense applications where extreme reliability and durability are required to ensure national security (Lopez, 2021). In addition to operational safety considerations there is a trend in the aerospace industry referred to as "More Electric Aircraft/All Electric Aircraft" ("MEA/AEA") toward higher levels of onboard electric power and increased reliance on electrically-actuated control systems to replace heavy hydraulic systems in aircraft. This trend is driven by the need to reduce weight, reduce fuel consumption, and reduce greenhouse gas emissions. This trend is in line with the goals outlined in the EU Green New Deal to reduce transportation-related greenhouse gas emissions by 90% in 2050 (Commision, 2021). Current mid-size aircraft like Airbus A320 or Boeing 737 electrical power distributions systems operate at a level of 0.5 megawatts ("MW") of power and maximum direct current ("DC") voltage of 270 volts ("V") DC. The Boeing 787 has 1 MW of onboard electrical power and will operate at a maximum DC voltage of 1000 V. In pursuit of the goals of reducing fuel consumption and greenhouse gas emission, it is expected that there will be a transition to Hybrid Electric Propulsion ("HEP") and ultimately a transition toward All Electric Propulsion ("AEP") in commercial aircraft. NASA has estimated that electric power levels of 10 MW and voltages of 6000 V DC will be needed to fully implement HEP and AEP propulsion in future midsize commercial aircraft. (B. Sarlioglu, 2015) (Hall, 2019) (Madonna, 2018) (Gemin, 2015) (Lopez, 2021; Lizcano, 2022) Failure in electrical insulation used to carry high-voltage or high-power levels can occur through sudden catastrophic "dielectric breakdown", through slow failure over time called "partial discharge failure", or through "tracking", which refers to the discharge of current along the surface of the insulation, causing degradation over time. Of these basic failure pathways, partial discharge failure, and tracking are the most difficult to mitigate. The key material properties needed to resist these failure pathways are: low dielectric constant of 2.1 to 2.6, high dielectric breakdown voltage of 20-100 V/micron, resistance to thermal degradation at high temperatures of 240C to 300C, resistance to dissolution by nearly all solvents, strength, flexibility and toughness at low temperatures of -56C, low surface energy of 18-20 milliJoule per square meter ("mJ/m2"), and hydrophobicity of a 90 degree to 120 degree water contact angle. This collection of material properties is unique to PTFE and similar fluoropolymer materials. (Cotton, Gardner, Schweikart, Grosean, & Severns, 2016) (Riba, 2020) (Moffat, Abraham, Desmulliez, Koltsov, & Richardson, 2008) (Lopez, 2021) The effectiveness of fluoropolymers as electrical insulation has its origin in the fact that fluorine is the most electronegative element on the periodic table. Electronegativity is a measure of the propensity for an atom to attract electron density from a neighboring atom when forming a covalent chemical bond. When bonded to a carbon atom, fluorine pulls the valence electron density of the carbon atom strongly toward itself resulting in a covalent bond with a partially ionic character. 4 2225 W. Chandler Blvd | Chandler, AZ USA This characteristic of the carbon-fluorine bond yields the strongest covalent chemical bond in organic chemistry. The strength of the carbon-fluorine bond gives very high thermal stability. It also results in a low dielectric constant and high dielectric strength; it is less likely that electrons will be displaced away from the carbon-fluorine bond causing charge separation when the material is placed in an electric field. No other chemical bond in organic chemistry has this attribute to the same degree and there is no possibility of finding an atom electronegativity pairing similar to the carbon-fluorine couple. The strength of the carbon-fluorine bond also yields extremely high resistance to chemical challenges like strong bases and acids; high resistance to solvation by liquid solvents; low surface energy; and flexibility and toughness at low temperatures. (Olabisi & Adewale) Alternative Materials Technologies for Aerospace & Defense Wire and Cable Applications Many other polymers have been proposed and tested as alternative electrical insulation materials for critical aerospace and defense applications: silicones, polyimides, cyclic olefins, and polyaryletherketones) to name a few (Lopez, 2021) (Lizcano, 2022; Borghei, 2021). Although these materials are useful building blocks for electrical insulation material technologies, none of them have the collection of advantageous materials properties demonstrated by PTFE and similar fluoropolymers, like PFA, FEP and ETFE. In addition, the aromatic backbone present in polyimides, cyclic olefins, and polyarylether ketones has been found to trend to low resistance to dielectric breakdown, partial discharge failure, and tracking failure. In practice these alternative polymer electrical insulation materials are typically combined with fluoropolymers in layered structures to accomplish specific engineering design goals like abrasion resistance or enhanced thermal conductivity. However, they are not adequate to provide the robust performance and durability required of a flight-critical system. Polyimide and silicone polymers contain carbonhydrogen bonds and silicon-hydrocarbon bonds that are susceptible to being broken by relatively low-energy events such as ultraviolet light exposure and lower-energy partial discharge events. The degraded polymer loses mechanical strength and flexibility, becomes more hydrophilic, and the resistance to dielectric breakdown and partial discharge is reduced. (Moffat, Abraham, Desmulliez, Koltsov, & Richardson, 2008) (Riba, 2020) III. Socioeconomic Impact to the EU In addition to current applications listed herein, fluoropolymer-based electrical insulating materials are also critical to achieve the EU Green Deal objectives. As part of the EU Green Deal, the EU has pledged to achieve a 90% reduction in greenhouse gas emission in transport by 2050. Aerospace transport contributes 3.8% of total CO2 emission and 13.9 % of transport emissions (Commision, 2021). In addition, the future EU transportation system has been pledged to be a `smart mobility' system that uses the full potential of data to integrate electronic ticketing and paperless freight transactions. This automated mobility is targeted for deployment on a large scale by 2030 (Communication, Directorate-General for, 2023). Beyond mobility, the EU Green Deal also features an industrial strategy for a globally competitive, green, and digital Europe. The pledge 5 2225 W. Chandler Blvd | Chandler, AZ USA is for European industry to be greener, more circular, and more digital while remaining globally competitive (Directorate-General for Communication, 2023). Fluoropolymer-containing components are critical to achieving these targets in mobility and digitization. Fluoropolymer-based electrical insulation materials are used in embedded aviation and automotive electronics, enabling the safety and communication features required to increase mobility. The same type of electrical insulation materials are also the enabling materials that will allow for smart mobility, and execution on vehicle-to-vehicle and vehicle-to-grid communications that must be robust across all operating environments, especially for aviation and automotive use applications. For digitization, fluoropolymer-based electrical insulation materials are essential in enabling 5G data transfer speeds. These materials are used across the wired infrastructure. This higher speed of data transfer is necessary to make the EU a world leader in fully automated and connected mobility systems, as outlined in the European Commission's Digital Strategy (Directorate-General for Communication, 2023). According to market reports, the current European Electrical Market size is estimated to reach 335 billion by 2027. This market space covers industrial manufacturing, automotive, healthcare, and aviation, to name a few (Europe Electrical Components Industry Outlook - Forecast (20222027), 2022). This industry has a direct impact of 3.8 trillion, which is approximately 20% of European GDP (Mitchell, 2021). For each application discussed above, development of an alternative would require significant investment in time (minimum of 5 years), materials (alternative resins are not currently commercially available), and cost to replace. It would likely cost about 1.5M per application to develop an alternative, and a minimum of 250M per customer application to qualify. In addition, it is very unlikely that a `one size fits all solution' will be identified as a PTFE replacement, as it is a very unique material, and used in a variety of electronic and electrical applications. The aerospace industry has been evaluating PTFE alternatives for over 30 years and have not found suitable replacement products meeting all the requisite application needs. Although there are other dielectric polymer materials that meet some of the performance requirements of aerospace & defense wire and cable applications, PTFE is required for the most demanding applications described herein due to the high voltage requirements, low and high temperatures, and pressure excursions experienced during flight, as well the need for robust performance in flight critical systems. It is highly uncertain that replacement materials can be developed or found for these applications if PFASs (in this specific case PTFE FEP, ETFE and PFA) are banned from use in aerospace and defense electrical insulation applications. IV. Comment on Annex Proposal Derogations For the aerospace & defense applications described herein, no derogation is currently proposed in the REACH proposal. This is untenable, as alternative materials are not currently available for these applications. 6 2225 W. Chandler Blvd | Chandler, AZ USA Therefore, we request: I. The exclusion of the following fluoropolymers from the proposed restrictions of the Annex XV Report on PFASs: a. polytetrafluoroethylene ("PTFE") CAS # 9002-8-0 (CF2CF2)n; b. perfluoroalkoxy alkane ("PFA") CAS # 26655-00-5 (CF2CF2)n-(CF2CF(OCF3))m; c. fluorinated ethylene propylene ("FEP") CAS # 25067-11-2 (CF2CF2)n(CF2CF(CF3))m; and d. Ethylene tetraflouroethylene ("ETFE") CAS # 25038-71-5 (CF2CF2 CH2CH2)n. As a result of their very high molecular weight, generally over 100 kg/mol, fluoropolymers have unique properties that distinguish them from all other PFASs. Fluoropolymers have a low impact to human health and the environment, as has been further detailed in this white paper. Thus, grouping fluoropolymers together with all other classes of PFASs for a single approach structure-hazard assessment based on persistence alone is not scientifically appropriate. II. Request for a temporary exemption for use of specific fluoropolymer PFASs in electronic applications We request that the proposed restrictions on PFASs provide a temporary exemption for "aerospace & defense wire and cable" uses of at least 20 years for: I. polytetrafluoroethylene ("PTFE") CAS # 9002-8-0 (CF2CF2)n; II. perfluoroalkoxy alkane ("PFA") CAS # 26655-00-5 (CF2CF2)n-(CF2CF(OCF3))m; III. fluorinated ethylene propylene ("FEP") CAS # 25067-11-2 (CF2CF2)n- (CF2CF(CF3))m; and IV. Ethylene tetraflouroethylene ("ETFE") CAS # 25038-71-5 (CF2CF2 CH2CH2)n. PFASs, and in particular the fluoropolymers listed above, are critical to a broad array of wire and cable components used in the aerospace & defense industry due to a unique combination of the following properties: I. Low dielectric constant and low dissipation factor enabling superior performance as wire & cable insulation. II. High dielectric strength enabling superior performance as wire & cable insulation. III. High resistance to failure by partial discharge and corona discharge enabling superior performance as wire & cable insulation. IV. Hydrophobic surface of about 18-20 mJ/m2 increases resistance to failure by surface tracking enabling superior performance as an electrical insulator at cable terminations. 7 2225 W. Chandler Blvd | Chandler, AZ USA V. Stable over varying environmental conditions such as high altitude/low atmospheric pressure, high humidity, and temperatures from -55C to 260C, enabling stable performance during environmental excursions. VI. Inherently flame retardant, eliminates need to include halogens and other fire retardant additives of high environmental risk. VII. Due to this unique combination of properties, PTFE, PFA, FEP, and ETFE are extremely difficult to substitute in specific aerospace & defense wire and cable components without significant tradeoffs in performance and lifetime as there are no known alternatives that meet all of these performance criteria. Significant invention is required to identify, and then qualify, each specific PFAS-free solution and there is no guarantee that such efforts will be successful. To date, no other class of materials has been able to demonstrate the collective performance benefits of the fluoropolymers listed above. Typical qualification and test cycles for specific aerospace & defense wire and cable component applications are in the five- to ten-year range. However, spare parts are required to be provided for up to 20 additional years for any units in the field. This requirement necessitates the extended derogation request to avoid interruption that could have significant impact to critical aerospace and defense needs. 8 2225 W. Chandler Blvd | Chandler, AZ USA References: References Agency, E. C. (2023). Annex XV Restriction Report. Helsinki, Finland: echa.europa.eu. B. Sarlioglu, C. T. (2015, June). More Electric Aircraft: Review, challenges, and opportunitiesfor commercial transport aircraft. IEEE Transactions Transport, Electric, 1(1), 54-64. Board, N. T. (1996). In fligth breakup over the Atlantic Ocean Trans World Airlines flight 800 Boeing 747131, N93119 Near East Moriches. New York: National Transportation Safety board. Borghei, M. (2021). 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