Clariant introduces PFAS-free PPA for PE film extrusion

Clariant has presented AddWorks PPA 101 FG, a PFAS-free polymer processing aid for polyolefin extrusion applications based on the company’s proprietary organic material technology. The product is intended for polyethylene blown and cast film, where it addresses melt fracture, commonly referred to as sharkskin, and helps prevent die build-up. Fluoropolymer-based polymer processing aids have been used for decades to manage these production issues, but tightening global PFAS regulations and selective bans in some regions and applications are supporting a gradual phase-out of conventional fluoropolymer technology. AddWorks PPA 101 FG is suitable for LLDPE-based packaging, agricultural and building and construction film applications, among others. According to Clariant, unlike fluoropolymer-based PPAs, it contains no PFAS, silicone or inorganic substances, is non-hazardous and label-free, and has food contact approvals under FDA, EFSA, Mercosur, China GB and Japanese regulations.

Regulatory context for PFAS-free processing aids

Fluoropolymer-based polymer processing aids have long been effective tools in PE film extrusion. The challenge is that they contain per- and polyfluoroalkyl substances, PFAS, substances described as highly persistent in the environment and harmful to human, animal and plant life. Regulators across the EU, USA and Asia are progressively restricting PFAS use across chemical sectors, and polymer additives are within scope.

PE film converters supplying packaging markets face both restrictions on PFAS in additives and recyclability requirements under the EU Packaging and Packaging Waste Regulation, PPWR. These requirements create additional incentives to eliminate PFAS from packaging film formulations.

Product characteristics and processing mechanism

AddWorks PPA 101 FG is a 100% active fine grain formulation with an approximate bulk density of 500–600 g/l. It lowers apparent shear stress at the extruder die wall, which raises the critical shear rate and allows higher output without melt fracture. Sharkskin removal typically begins 20 to 40 minutes after line start-up, depending on let-down ratio, LDR, resin type, film configuration, and process and equipment parameters.

At a 0.2% LDR, performance is described as near-equivalent to conventional fluoropolymer-based PPAs in critical shear rate testing. The product is thermally stable, with less than 0.5% weight loss below 280°C and less than 0.9% below 320°C. It can be incorporated via the host resin, as a concentrate or via a masterbatch carrier.

AddWorks PPA 101 FG typically works in Ziegler-Natta LLDPE as well as in more difficult-to-process metallocene LLDPE resins, including fully formulated film configurations without antagonistic effects with typical film co-additivation.

Use in film and pipe extrusion

In polyolefin extrusion, the product is intended to eliminate sharkskin through melt fracture control at standard production output rates and to reduce die build-up, with performance tunable through LDR and process conditions. Clariant also points to improved film surface smoothness and quality, with improved haze compared with neat LLDPE, supporting downstream film converting.

The company states that AddWorks PPA 101 FG has no negative effect on film optics, coefficient of friction, CoF, dyne level or tensile properties. It is also described as not interfering with typical post-treatment operations, including corona treatment, printing, lamination and heat-sealing. Its absence of silicone and polysiloxane substances is relevant for film converters using corona treatment or adhesive lamination, who have cited contamination risk as a reason to avoid silicone-based PFAS-free alternatives.

In LLDPE blown film for packaging, sharkskin and die build-up are frequent causes of film quality issues as well as production slowdown or downtime. AddWorks PPA 101 FG is intended to resolve these issues while maintaining the optical film quality and mechanical properties required for consumer and industrial packaging films. Other blown film applications include agricultural PE films, such as mulch film, silage film and greenhouse covering, and construction films, including vapor barriers and protection films requiring consistent processability and film integrity.

In LLDPE cast film production, die build-up control is important for managing die service life, extending die cleaning intervals and avoiding excessive cleaning stops. Clariant reports that AddWorks PPA 101 FG has been validated and adopted in cast film production on the basis of die service interval improvements while maintaining optical film quality. The product is described as thermally stable for cast lines operating at melt temperatures up to 280°C or higher without causing chill roll deposits. In industrial stretch film applications, it is reported to show no negative impact on film stretch behaviour.

Beyond film, proof-of-concept work in HDPE pipe extrusion is showing encouraging early results. Efficient processing and smooth inner pipe surfaces are described as key performance requirements, and initial trials across multiple regions indicate that AddWorks PPA 101 FG can address both.

"The regulatory pressure is the driver, but the product must deliver the needed performance. AddWorks PPA 101 FG handles melt fracture and die build up challenges without interference with the film properties and behaviors, providing film producers the opportunity to eliminate PFAS," says Diederik Goyvaerts, Market Manager, Clariant Additives.

Expert Q&A with Diederik Goyvaerts

What is the difference between AddWorks PPA 101 FG and AddWorks PPA 122 G?

AddWorks PPA 101 FG is a 100% active fine grain used in EMEA, Americas and SEAP markets. AddWorks PPA 122 G is a ready-to-use PE-based masterbatch using the same proprietary technology, targeted primarily at Greater China and SEAP. Both products are PFAS-free and contain no silicone, polysiloxane or inorganic substances.

Can AddWorks PPA 101 FG be used as an ingredient in masterbatch production?

Yes. Its fine grain format is designed for flexible incorporation, including as the active ingredient in PFAS-free PPA masterbatch formulations that masterbatch producers develop for their film converter customers. Alternatively, it can be incorporated directly into a host resin ex-works by resin producers. In such cases it is offered to the market as a ready-to-use resin.

Why is the absence of silicone and polysiloxane highlighted?

Alternative PFAS-free processing aid technologies can be based on polysiloxane and/or silicone chemistry. The film producing industry typically tries to avoid these chemistries because of production line contamination concerns and possible interference with downstream film post-treatments, including printing, lamination and sealing.

Is AddWorks PPA 101 FG a drop-in replacement for fluoropolymer-based PPAs?

AddWorks PPA 101 FG uses different chemistry compared with fluoropolymer-based PPAs and will require some familiarisation and minor adjustments in the way it is used in film extrusion. Loadings are typically higher, in the range of 0.1 to 0.3%, while sharkskin removal time is expected to be largely similar to fluoropolymer PPA references. The overall cost-in-use is expected to be at the same level.

Is AddWorks PPA 101 FG suitable for food packaging applications?

Yes. AddWorks PPA 101 FG is non-hazardous, label-free and holds broad food approvals across five major food contact jurisdictions:

• EU: listed on Annex I of Regulation (EU) 10/2011, EFSA.
• USA: approved for polyolefins per 21 CFR 177.1520, FDA.
• Mercosur: cleared for all plastics.
• China: listed under GB 9685-2016 for polyolefins.
• Japan: MHLW Positive List, issued November 2023.

For more information on food approvals, Clariant recommends contacting a local company representative.