PFAS-Free Processing Aids: 5 Chemistries, PPWR Limits and How to Switch

PFAS-free processing aids are non-fluorinated polymer processing aids, mainly polyether-siloxanes, boron nitride, thermoplastic polyurethane, modified polyolefin or ester masterbatches and, in research, hyperbranched polymers, that replace fluoroelastomer PPAs in polyolefin extrusion by coating the die wall and suppressing sharkskin melt fracture. They exist because the additive they replace is itself a PFAS, so the real question is what changed in the regulation and whether the substitute holds the line speed.

A polymer processing aid is one of the few plastic additives that is dosed at parts per million yet decides whether a blown-film line runs at all. Since 12 August 2026, Article 5(5) of Regulation (EU) 2025/40 (PPWR) bars food-contact packaging from the EU market above 25 ppb for any single targeted PFAS, 250 ppb for the sum of targeted PFAS, or 50 ppm for all PFAS including polymeric PFAS, and a fluoroelastomer PPA is a polymeric PFAS.

This page sets out the 5 non-fluorinated chemistries, their published performance against the fluoropolymer incumbent, how much of each is used, how a line is converted, which grades clear food contact, and how a converter proves the line is PFAS-free.

Key figures

• 5 non-fluorinated processing-aid chemistries replace fluoroelastomer PPAs in polyolefin extrusion: polyether-siloxanes, boron nitride, thermoplastic polyurethane, modified polyolefin or ester masterbatches, and hyperbranched polymers.
• 50 ppm is the total-PFAS limit, including polymeric PFAS, for food-contact packaging placed on the EU market since 12 August 2026 (Regulation (EU) 2025/40, Article 5(5)).
• 0.2 wt% (2,000 mg/kg) is the FDA legal maximum for the VDF-HFP fluoroelastomer extrusion aid being replaced (21 CFR 177.1520).
• 0.005 to 0.5% is the published boron nitride loading range that removed surface melt fracture in metallocene polyethylene (Rosenbaum et al. 2000).

What Is a PFAS-Free Processing Aid?#

A PFAS-free processing aid is a polymer processing aid that performs the die-wall function of a fluoroelastomer PPA without containing per- or polyfluoroalkyl substances, and the term is defined by exclusion, which is why the same product is sold as fluorine-free, non-fluorinated or non-PFAS. The US FDA covers the same function under a different name: 21 CFR 177.1520 lists it as an "extrusion aid", and that wording, not "PFAS-free", is the phrase to search for inside the CFR itself.

The word "PPA" is ambiguous, since it also stands for a substance regulated under EU 10/2011 Article 3(8), and for a chemistry used in a different polymer. Table T1 disambiguates the four things "processing aid" can mean.

Table T1. What "processing aid" means

What does a polymer processing aid do in the first place?#

A polymer processing aid works at the die wall, not in the bulk melt: the additive is immiscible with the polyethylene, its droplets migrate to the metal under flow, and the low-energy coating they form lets the melt slip instead of sticking. Kharchenko, McGuiggan and Migler at the National Institute of Standards and Technology used frustrated total internal reflection imaging in 2003 to confirm the migrating species collects at the die wall rather than acting inside the bulk melt. How thick the coating builds before melt fracture clears governs the conditioning period known as time-to-clear.

The mechanism runs in 3 steps.

1. Droplets of the immiscible processing aid migrate through the polyethylene melt toward the metal die wall under shear.
2. The droplets coalesce into a continuous, low-surface-energy coating on the die land.
3. The coating lets the bulk melt slip at the wall instead of sticking, which raises the critical flow rate for melt fracture and increases output at a given screw speed.

Without a processing aid present, the melt reaches its critical wall shear stress sooner and the extrudate leaves the die with visible distortion. The hub on polymer processing aids covers the acrylic PVC type and the flow enhancers as well; across the family this same mechanism delays the onset of flow instabilities and increases output, a relationship Morris documented in 2024 in the Journal of Vinyl Additive Technology.

Why fluoropolymer processing aids count as PFAS#

A fluoropolymer processing aid is a vinylidene fluoride and hexafluoropropylene copolymer (CAS 9011-17-0) whose FDA-specified grade is 65 to 71 percent fluorine by weight, so it falls inside the structural definition of a per- or polyfluoroalkyl substance and counts as a polymeric PFAS. The commercial name most converters know is Dynamar, sold in grades FX 5920A, FX 5922, FX 5924, FX 9613 and FX 9614, plus a fluoroelastomer terpolymer, FX 5911 (CAS 25190-89-0). The identity holds regardless of grade, because every VDF-HFP copolymer in this fluorine range shares the same polymeric-PFAS classification under the PPWR.

Table. Fluoroelastomer PPA identity

Polymers are exempt from REACH registration under Article 2(9), which is why this fluoroelastomer carries no registration dossier of its own, even though its monomers do. On food-contact packaging, the fluoroelastomer itself is not individually listed as an additive in Annex I of EU 10/2011; only its monomers appear, vinylidene fluoride as FCM 132 (SML 5 mg/kg) and hexafluoropropylene as FCM 282 (not detectable), and how the additive itself clears the Union list is not established. Grade-level cross-references and the full Dynamar product line are covered on fluoropolymer processing aids (PPA).

Are all processing aids PFAS?#

No: only the fluoropolymer type is a PFAS, and the acrylic processing aids used in rigid PVC, the waxes and metal soaps used as lubricants, and every chemistry described on this page contain no fluorine at all. Fluorine chemistry is a choice made only inside the polyolefin die-wall category, not a property of the processing-aid function itself.

Why Converters Are Switching: PPWR, REACH, TSCA and the 3M Exit#

Converters are switching for two separate reasons: one regulation with a date that has already passed, and one supplier decision that removed the market's benchmark product. Buyers should separate the two drivers, because a compliance deadline and a discontinued grade need different lead times to plan against.

Table T2. Regulatory and supply timeline

Dates are the instrument's own; check the Official Journal or the Federal Register before relying on a pending item.

EU PPWR: the PFAS limits for food-contact packaging since 12 August 2026#

Since 12 August 2026, Article 5(5) of Regulation (EU) 2025/40 has barred food-contact packaging from the EU market when it contains PFAS at or above 25 ppb for any single substance measured by targeted analysis, 250 ppb for the sum of targeted substances, or 50 ppm for all PFAS including polymeric PFAS. The three limits apply together, and they work in the following order.

• 25 ppb for any single PFAS measured by targeted analysis, with polymeric PFAS excluded from quantification at this step.
• 250 ppb for the sum of all targeted PFAS found by that same analysis.
• 50 ppm for total PFAS, and this figure does include polymeric PFAS.

If total fluorine exceeds 50 mg/kg, the manufacturer shall, on request, prove how much is PFAS and how much is not. The third limit is the one that reaches a processing aid, and this is this site's own reading, not legal text: the 65 to 71 percent fluorine grade is permitted by FDA up to 0.2 wt% of the polymer, 2,000 mg/kg, so loadings in the hundreds of ppm sit in the same order of magnitude as the 50 ppm limit. That proximity is why the PPWR is the single biggest driver of PFAS-free PPA demand in EU food-contact film. No Commission guidance on measuring "total PFAS", or on a multilayer laminate, is in our source library. Recycled-content and substance-of-concern duties under the EU Packaging and Packaging Waste Regulation (PPWR) apply to the same packaging.

The EU universal PFAS restriction under REACH#

The EU universal PFAS restriction is still a proposal, not a rule: five member states submitted it to ECHA in 2023, the 2025 update sets out four options ranging from a full manufacturing ban to unlimited manufacturing with emission controls, and a Commission draft and a REACH Committee vote are the next steps. Fluoropolymers used as a PPA fall inside the proposal's group definition, while industry argues fluoropolymers are polymers of low concern, a position set out by Korzeniowski and colleagues in a 2022 paper in Integrated Environmental Assessment and Management. The RAC final opinion was adopted on 2 March 2026 and the SEAC draft opinion was agreed on 10 March 2026 and published on 26 March 2026, open for consultation until 25 May 2026, with the final SEAC opinion expected at the end of 2026. Nothing is in force, so a PPA decision made today is made against a proposal, not a rule.

The full status of every instrument is tracked under PFAS restrictions and plastic additives: never read this proposal as a ban. The binding instrument that already applies to a processing aid is the PPWR, not this restriction, and no fluoropolymer PPA "will be banned in 2026" under REACH.

United States: TSCA 8(a)(7) reporting and state PFAS laws#

In the United States there is no PFAS limit for a processing aid, but there is a reporting duty: the TSCA section 8(a)(7) rule of 11 October 2023 covers every PFAS and every PFAS-containing article manufactured or imported since 1 January 2011. Reporting scope and the risk-evaluation programme are explained on TSCA and plastic additives. EPA proposed exemptions in November 2025 for PFAS at 0.1% or less in mixtures, imported articles, byproducts, impurities, R&D uses and non-isolated intermediates, and comments closed 29 December 2025. The April 2026 final rule (91 FR 18786, effective 13 April 2026) moved the reporting submission period to 31 January 2027, or 60 days after EPA's forthcoming substantive rule, whichever is earlier.

Three states moved ahead of the federal duty with staged bans on products containing intentionally added PFAS: Minnesota's Amara's Law runs 1 January 2025 to 1 January 2032, fee and reporting rule adopted 8 December 2025; Maine's schedule reaches all products by 1 January 2032 unless a currently unavoidable use applies; Washington's Safer Products Cycle 1.5 was adopted 20 November 2025, effective 21 December 2025. None of these three laws names polyolefin film or a processing aid specifically, so US state laws on plastic additives is the page to check how each is scoped.

Supply side: 3M's exit from PFAS manufacturing#

The second driver is commercial: 3M announced on 20 December 2022 that it would leave PFAS manufacturing, including fluoropolymers and PFAS-based additive products, by the end of 2025, removing the Dynamar line that most fluoropolymer PPA grades were benchmarked against. That single announcement, worth about USD 1.3 billion in annual PFAS net sales to 3M, did more to move converters toward a non-fluorinated grade on a fixed timeline than any regulation published before it. Other fluoropolymer PPA suppliers exist, but their product status after the exit is not established in our source library, so none is named as a current alternative source.

What Are the 5 Types of PFAS-Free Processing Aids?#

The 5 types of PFAS-free processing aid are polyether-siloxanes, boron nitride, thermoplastic polyurethane, modified polyolefin and ester masterbatches, and hyperbranched polymers, and only the first four are on the market. They are ordered here by commercial and evidential weight, starting with the chemistry that already carries an FDA food-contact listing, moving through the chemistries with the strongest published performance data, and ending with the one still confined to research.

Table T3. The 5 PFAS-free PPA chemistries

Published loadings come from the cited studies and from the CFR. The CFR figures are legal maxima, not recommended dosages. Trials decide the final level.

1. Polyether-siloxane and silicone processing aids#

Polyether-siloxane processing aids work the same way the fluoropolymer does, by forming a low-surface-energy film at the die wall, and one of them has been in the US food-contact rules longer than the PFAS debate: polyoxyethylene-grafted polydimethylsiloxane, CAS 68937-54-2, is listed as an extrusion aid for olefin polymers at up to 0.3 percent by weight under 21 CFR 177.1520. The base polymer behind that grafted grade, polydimethylsiloxane (PDMS), carries CAS 63148-62-9 and is what supplies the low-surface-energy siloxane film at the interface. Under EU 10/2011, PDMS is FCM 575, restricted to a molecular weight above 6,800 Da and a viscosity of at least 100 cSt at 25°C, which keeps the low-molecular-weight, more mobile fractions out of the food-contact route. A 2026 review by Donahue-Boyle and colleagues in RSC Sustainability places siloxanes among the chemistries being evaluated as PFAS alternatives across several industries, processing aids among them.

Regulatory listing is not the same thing as a solved problem, because a silicone processing aid still has to match a fluoropolymer's conditioning behaviour on the actual line, and that comparison is addressed later on this page. Grades, viscosity classes and the FCM 575 restriction in full are set out on the polydimethylsiloxane (silicone oil) substance page, which is the reference for this chemistry.

D4, D5 and D6: the REACH catch in silicone processing aids#

A silicone processing aid solves the fluorine problem but inherits a siloxane one: since 6 June 2026, octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) may not be placed on the EU market in mixtures at 0.1 percent by weight or more, under REACH Annex XVII entry 70 as amended by Regulation (EU) 2024/1328. Later dates apply to specific uses: leave-on cosmetics reach the limit on 6 June 2027, medical devices and medicinal products on 6 June 2031. Derogations exist for industrial uses and some residues remaining in silicone-polymer mixtures, up to 1% for adhesion, sealing, gluing and casting uses, up to 0.5% D4 or 0.3% D5/D6 for protective coatings, and up to 0.2% for devices. All three have been on the SVHC Candidate List as PBT and vPvB substances since 27 June 2018.

Buyers should ask for the residual D4, D5 and D6 content of a silicone PPA masterbatch in writing, since the entry applies to the mixture placed on the market, not only the pure monomer. Entry 70 sits alongside the other additive entries under REACH Annex XVII restrictions.

2. Boron nitride (h-BN)#

Boron nitride is the best-documented non-fluorinated processing aid: at 0.005 to 0.5 percent it removed surface melt fracture and pushed back gross melt fracture in metallocene polyethylene and FEP, in work by Rosenbaum, Randa, Hatzikiriakos, Stewart and Henry published in Polymer Engineering and Science in 2000. Hexagonal boron nitride (h-BN) carries CAS 10043-11-5, EC 233-136-6, formula BN, molecular weight 24.82 g/mol. The effect is governed by the balance of polar and dispersive surface energy at the die wall, a mechanism Rathod and Hatzikiriakos characterised in 2004, and Muliawan, Hatzikiriakos and Sentmanat described boron nitride in 2005 as an energy dissipater against gross melt fracture specifically.

Boron nitride combined with a small amount of fluoroelastomer outperforms either used alone, a synergy reported by Seth at the University of British Columbia in 2011 and by Rathod and Hatzikiriakos in 2004; that hybrid is not a PFAS-free route, since it still contains fluoropolymer, and is noted only for completeness. On the regulatory side, boron nitride is listed in EU 10/2011 as FCM 583 under group restriction 16, migration limit 6 mg/kg as boron, and FDA's FCN 970 caps it at 1 wt% for a polyhydroxyalkanoate nucleator use, a clearance that must never be read as covering a PPA application. Its REACH registration position, per a 2026 ECHA CHEM query, showed 26 active dossiers under EC list 701-292-9 and none under EINECS 233-136-6, though that single-query result is unconfirmed.

3. Thermoplastic polyurethane (TPU)#

Thermoplastic polyurethane deposits on the die in the same way and, in work published by Kulikov in 2005, postponed sharkskin to an extrusion rate 12 to 20 times higher, which is why it was proposed then as a cost-effective substitution for fluorinated polymers. TPU is not a single CAS-numbered substance, because its properties depend on the diisocyanate, polyol and chain-extender chemistry used to build it, so no single loading figure applies across grades. Our source library holds no TPU loading for a current PPA use, no food-contact position for this specific application and no current commercial grade sold as a TPU processing aid, so the honest statement is that TPU remains a published result rather than an available product line today.

4. Modified polyolefin and ester masterbatches#

The products most converters actually buy are proprietary masterbatches based on modified polyolefins and esters, launched in a tight cluster: Techmer PM in February 2023, Ampacet during 2023, Baerlocher USA's Baerolub AID on 29 November 2023 and Clariant's AddWorks PPA at Chinaplas on 23 April 2024. Carrier resins and let-down conventions for this masterbatch format in general are covered under additive masterbatch, which applies to any additive delivered this way, not only a processing aid.

None of these suppliers publishes the chemistry, the active content or a use level. That is the single biggest gap in the public record on PFAS-free PPAs, and it is why a trial on the actual resin and die is not optional before a line change is committed to.

5. Hyperbranched polymers (research stage)#

Hyperbranched polymers with C16 or C20/22 alkane end groups eliminated melt fracture in LLDPE at loadings up to 10 percent and needed almost no preconditioning, in work by Hong, Cooper-White, Mackay, Hawker and Malmström published in the Journal of Rheology in 1999, but they have stayed a research chemistry since. That 10 percent figure is two orders of magnitude above a commercial PPA level, which is typically dosed in parts per million to low tenths of a percent, so the number belongs to a laboratory paper and should not be read as a recommendation for line dosing.

Do PFAS-Free PPAs Work as Well as Fluoropolymer PPAs?#

The published answer is partial: PFAS-free processing aids do clear melt fracture, and they are generally reported to need longer conditioning, a higher loading, or both, but the size of that penalty is not in the public record in a form this page can quote. Table T4 sets out what is documented for each side of the comparison and where the record stops.

Table T4. Fluoropolymer PPA vs. PFAS-free PPA

Time-to-clear and slip velocity: what the measurements show#

Time-to-clear is the conditioning time a line needs before melt fracture disappears, and it decides whether a PFAS-free grade is usable: Yang, Arefi, Gritsichine and Tzoganakis at the University of Waterloo measured slip velocity and time-to-clear for non-PFAS processing aids in blown-film extrusion and published the results in the Journal of Plastic Film and Sheeting in 2025. Because layer build-up at the die wall governs how quickly melt fracture clears, measuring slip velocity and time-to-clear is the direct way to quantify how a non-fluorinated chemistry compares with the fluoropolymer it replaces. The full magnitudes from that paper could not be verified against the primary source for this page, so no slip-velocity or time-to-clear figure is published here; what can be stated is what was measured and by whom, and that the qualitative direction, a longer conditioning period, matches what Morris reported in 2024 when describing the general challenge of understanding a new PPA technology's impact on performance.

Where fluoropolymer processing aids also fail#

The fluoropolymer is not a universal fix either: in work by Adesina, Nasser and Hussein published in 2015, a fluoropolymer PPA at 0.05 percent by weight did not eliminate stick-slip fracture in HDPE, and gross melt fracture returned at a shear rate of 141 per second. The same study found that combining an organoclay with the fluoropolymer reduced pressure fluctuations more than either additive did alone, which shows that the incumbent chemistry also needs help outside its core die-wall mechanism in some resins. Conventional polyolefin processing aids of either type are also ineffective in PMMA, where the critical shear stress for spiral and helical distortion is 0.35 ± 0.03 MPa, a figure established by Stamboulides and Hatzikiriakos in 2006. Without this evidence, the page would read as a defence of the fluoropolymer rather than an honest comparison; the identity, FDA specification and TSCA position of the fluoroelastomer processing aid are set out in full on its own substance page.

How Much PFAS-Free Processing Aid Does Polyethylene Need?#

Polymer processing aids are dosed in parts per million, not percent: the published reference points are 500 ppm in the fluoropolymer study by Adesina and colleagues, 0.005 to 0.5 percent for boron nitride, and the US legal ceilings of 0.2 percent for the VDF-HFP grade and 0.3 percent for the polyoxyethylene-grafted silicone. Four factors drive where a real line lands inside or beyond that range.

• Resin family: metallocene and linear low-density polyethylenes reach melt fracture at lower flow rates than conventional LDPE, so they generally need the processing aid active sooner.
• Die geometry: a longer, higher-surface-area die land takes longer to coat, extending the conditioning period.
• Line output target: raising output raises the wall shear rate the coating has to withstand, which can call for a higher active loading.
• Let-down ratio of the masterbatch: the carrier resin and active content set how much of the final film is actually active processing aid, not a nominal percentage on the bag.

No supplier use level for a commercial PFAS-free PPA masterbatch is in our source library, so the only honest answer for those products is the let-down ratio on the technical data sheet, confirmed by a line trial. Blown film, pipe and cable levels by polymer type are compared on the processing aids for polyethylene page.

As a worked example only, a 3 wt% active PPA masterbatch let down at a 2% addition rate gives 600 ppm of active processing aid in the finished film (0.03 × 0.02 = 0.0006, or 600 ppm). This is a calculation example, not a supplier claim; check the arithmetic against the let-down ratio calculator before applying it to a real formulation.

How Do You Switch an Extrusion Line to a PFAS-Free PPA?#

Switching a line is not a drop-in substitution, because the additive being replaced is not in the melt but on the die wall, and the incumbent coating has to come off before the new one can build. The 5 steps below follow directly from that mechanism, and they are an engineering synthesis of the processing-aid science described earlier on this page, not a cited industry procedure.

1. Confirm the incoming resin has no processing aid already compounded into it.
2. Purge the die of the existing fluoropolymer coating before introducing the replacement.
3. Dose the PFAS-free replacement and allow a longer conditioning period than the fluoropolymer incumbent needed.
4. Check melt fracture, die build-up and head pressure at the target output, not a reduced one.
5. Re-check the downstream additives that share the die wall, such as slip and antiblock, for any interaction with the new coating.

Step 3 is usually the one converters underestimate, because the published record consistently reports longer conditioning for a non-fluorinated grade without giving a number a line manager can plan a changeover around.

Purging the fluoropolymer coating out of the die#

A fluoropolymer coating is a physical layer on the metal, so it leaves the same way it arrived, by being displaced over time at running conditions rather than by a single purge shot. The coating's own thickness governs how long the reverse process takes, following the same layer-build-up logic that governs time-to-clear. Deposits also concentrate where the melt experiences negative pressure at the die exit edge, a driving force documented by Musil and Zatloukal in 2013 and 2014, and that is where the incumbent coating clears last. Our source library holds no purge compound, time or temperature for this operation, so this page states what governs the process rather than inventing a procedure; the supplier's own line-start-up documentation covers the specific steps.

Interactions with antiblock, slip agents, pigments and fillers#

A processing aid shares the die wall with everything else that migrates there, which is why the same formulation change can fix melt fracture and start die build-up at the same time. Table T5 sets out what our source library documents about each co-additive's effect at the die.

Table T5. Co-additive and resin effects at the die

Antiblock particles are one route by which a formulation change elsewhere in the film can undo a processing aid's effect: antiblock additives decide how abrasive the melt is at the die through their particle hardness and loading.

Supplier literature names abrasive antiblocks such as talc and silica, and some HALS and pigments, as processing-aid antagonists, but our source library has not been able to confirm that against a primary technical data sheet, so the antagonist list is written here as an open trial variable rather than a rule. Synergy and antagonism across all additive families are mapped under additive interactions, which is the page to consult before ruling any combination in or out.

Which PFAS-Free Processing Aids Are Cleared for Food Contact?#

A processing aid for food-contact film has to clear two hurdles in the EU since 12 August 2026: the substance must be usable under Regulation (EU) No 10/2011, and the finished packaging must stay below the PPWR's PFAS limits. In the US, only 21 CFR 177.1520 and the adjacent CFR routes decide whether a grade may be used, and the trap on both sides of the Atlantic is the same: a substance-level listing says nothing about whether the finished article complies.

EU 10/2011 and the PPWR read together#

Boron nitride shows how the two instruments stack: it is listed in Annex I of Regulation (EU) No 10/2011 as FCM 583 under group restriction 16, with a total specific migration limit of 6 mg/kg expressed as boron, and because it contains no fluorine it adds nothing to the PPWR total. Table T6 lines up the substance-level clearance against the CFR route for every chemistry with a documented listing.

Table T6. Food-contact matrix

FDA figures are maximum use levels, not recommended dosages. Check the condition of use in 21 CFR 177.1520.

The generic EU 10/2011 overall migration limit of 10 mg/dm² applies across all of these substances unless a substance-specific limit overrides it. How FCM numbers, specific migration limits and group restrictions work in general is explained on EU 10/2011.

A food film's compliance file has to cover more than the processing aid alone: the whole set of clearances a food-contact film formulation needs, from resin to pigment, is collected on additives for food packaging.

FDA 21 CFR 177.1520 and the other 21 CFR routes#

In the United States both the fluorinated and the silicone route sit in the same rule: 21 CFR 177.1520 covers olefin polymers and lists the VDF-HFP copolymer as an extrusion aid at up to 0.2 percent by weight and polyoxyethylene-grafted polydimethylsiloxane at up to 0.3 percent. A separate route closed in 2024 and 2025: FDA determined 35 food-contact notifications for PFAS grease-proofing agents to be no longer effective, announced the market exit in February 2024 and published the determination in January 2025, and it is not an action against processing aids. The remaining authorised PFAS food-contact categories are non-stick cookware coatings, sealing gaskets in food processing equipment, and manufacturing aids for other food-contact polymers, all separate from a die-wall processing aid. The EVA route to the same fluoroelastomer chemistry, 21 CFR 177.1350, caps the VDF-HFP processing aid at 0.2 percent of the EVA. Conditions of use and the FCN route are decoded on FDA food contact rules for plastic additives (21 CFR).

How Do You Prove an Extrusion Line Is PFAS-Free?#

Proving a line is PFAS-free means two different things at once: the packaging has to survive an analytical check, and the line has to keep running without the additive that used to keep it clean.

Total fluorine screening and targeted PFAS analysis#

The PPWR sets the analytical order itself: a total-fluorine screen first, and if total fluorine exceeds 50 mg/kg the manufacturer must show, on request, how much is PFAS and how much is not. Polymeric PFAS are excluded from quantification in the targeted analysis that measures the 25 ppb and 250 ppb limits, but they are counted in the 50 ppm total-PFAS figure, which is why a fluoropolymer PPA is caught even though a targeted PFAS test alone would not detect it as an individual substance. The scale of the wider substance universe this sits inside is large: Wiesinger, Wang and Hellweg at ETH Zurich identified more than 10,000 plastic substances in a 2021 paper in Environmental Science and Technology, over 2,400 of potential concern, 901 approved for food-contact plastics in at least one jurisdiction, and processing aids accounted for 3,498 of the chemicals counted. Which method answers which PPWR limit is set out on PFAS testing of plastics and packaging; our source library names no specific laboratory, method detection limit or accreditation.

Checking the PPA still works: melt fracture and die build-up#

The four things to watch after a changeover are surface melt fracture at the die exit, gross melt fracture from the die entrance, head pressure oscillation, and the deposit that builds on the open faces of the die.

• Surface melt fracture (sharkskin), which originates at the die exit and gives the film a hazy, matte surface.
• Gross melt fracture, a volume distortion that originates at the die entrance rather than the exit.
• Stick-slip or spurt flow, shown as pressure oscillation and typical of linear polyethylene, as Hatzikiriakos and Dealy characterised in 1992.
• Melt flow rate against the resin's ISO 1133 or ASTM D1238 specification, with capillary rheometry to ASTM D3835, the method the CFR itself cites for the PPA grade specification.

The defect types and their critical stresses are covered in full on melt fracture and sharkskin.

Die build-up, more precisely die drool, is the unwanted spontaneous accumulation of extruded melt on the open faces of the die, driven by negative pressure at the die exit edge and first remarked on in 1946. It carries several working names on a shop floor: drooling, die lip build-up, die bleed, die plate-out, die deposit, die drip, die moustache and gummy crust. Causes and remedies for die build-up (die drool) are collected on its own page.

Who Supplies PFAS-Free Processing Aids?#

The PFAS-free processing aids we can document came from four suppliers inside fourteen months: Techmer PM in February 2023, Ampacet during 2023, Baerlocher USA with Baerolub AID on 29 November 2023 and Clariant with the AddWorks PPA line announced at Chinaplas on 23 April 2024. Company profiles and grade lists are in the directory of polymer processing aid suppliers, which covers the wider processing-aid supply base beyond this PFAS-free cluster.

Table T7. Documented PFAS-free PPA launches

Launch records from trade press. The list is not a market survey; see our methodology.

This is what our source library carries, not a market survey; other manufacturers market PFAS-free PPA grades not yet confirmed against a primary source here. Buyers should compare grades by let-down ratio, food-contact statement and residual D4, D5 and D6 content, since the chemistry itself is not disclosed by any of the four documented suppliers.

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Which Other Additives in a Polyethylene Film Can Contain PFAS?#

A processing aid is only one place fluorine enters a plastic: the rest of a polyethylene film package, from antioxidants to slip and antiblock, is fluorine-free, but other polymers carry PFAS additives of their own. The rest of the package is set out on additives for polyethylene (PE).

PTFE anti-drip and tribological additives#

The two other PFAS additives a compounder is likely to meet are polytetrafluoroethylene, used as an anti-drip agent and as a wear additive, and potassium perfluorobutane sulfonate, the flame retardant for polycarbonate. Polytetrafluoroethylene carries CAS 9002-84-0 and EC 618-337-2, and, being a fluoropolymer itself, falls within the scope of the EU universal PFAS restriction proposal described earlier on this page. Anti-drip dosage and PFAS status in full are set out on PTFE as a plastic additive. Potassium perfluorobutane sulfonate, also known as PFBS-K or Rimar salt, is a PFAS flame retardant used in polycarbonate, and PFBS and its salts have been on the SVHC Candidate List since 16 January 2020. PTFE competes in a wear-resistance role with silicone, molybdenum disulfide and graphite under tribological additives.

PFAS in the wider plastics and packaging value chain#

Outside the additive itself, PFAS reach packaging through grease-proofing treatments and fluorinated containers rather than through the polymer, which is why a PFAS-free additive statement and a PFAS-free package are two different claims. FDA's determination that 35 grease-proofer food-contact notifications were no longer effective, with the remaining authorised PFAS food-contact categories limited to non-stick cookware coatings, sealing gaskets and manufacturing aids, is the clearest example of that separate route. Every route PFAS take into a plastic article is mapped under PFAS in plastics, and slip, antiblock and antifog packages that share a film with a processing aid are covered on additives for packaging film.

Is PTFE a PFAS?#

Yes: polytetrafluoroethylene is a fluoropolymer and therefore a PFAS, and it falls within the scope of the EU universal PFAS restriction proposal, although that proposal is not yet a rule.

Is a "polymer production aid" the same as a polymer processing aid?#

No, and the collision matters in a compliance file: Article 3(8) of Regulation (EU) No 10/2011 defines a polymer production aid as a substance that provides a medium for making the polymer, such as a catalyst or an emulsifier, and it is not an additive at all.

Are PFAS-free PPAs the same as acrylic processing aids for PVC?#

No: acrylic processing aids are high-molecular-weight methyl methacrylate copolymers that work inside a rigid PVC melt to promote fusion, and they contain no fluorine either, but they were never a PFAS product and do not coat a die wall. Sombatsompop and Phromchirasuk documented their mechanism in 2004: MMA copolymers with ethyl or butyl acrylate raise fusion, melt strength and extrudate swell in rigid PVC and moderate sharkskin, at a dosage of 0.5 to 2.0 phr reported by a secondary supplier source rather than a primary paper. Fusion promotion and foam-cell regulation are covered on processing aids for PVC (acrylic processing aids).

Does a PFAS-free PPA make the whole film PFAS-free?#

Not by itself: the PPWR limits apply to the finished food-contact packaging, so removing the fluoropolymer processing aid closes the largest additive route into the film but does not answer for coatings, inks, treatments or a fluorinated container. A converter proving the finished packaging complies with the PPWR still has to check every other input to the package, not only the processing aid formulated into the resin.