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PFAS-Free Polymer Processing Aids (PPA) for PE Film Extrusion 

Fluoropolymer Replacement for Stable, High-Speed Film Processing

What problems limit PE film extrusion today?

Polyethylene (PE) film extrusion using LLDPE, HDPE, and mLLDPE is often limited by melt fracture, sharkskin formation, and unstable die flow under high-throughput conditions.

These defects are caused by interfacial friction instability between the polymer melt and the metal die surface, especially under high shear stress.

Fluoropolymer-based PPAs have historically been used to stabilize processing, but increasing PFAS regulatory pressure is accelerating the transition toward fluorine-free alternatives.

Why does melt fracture occur in PE film extrusion?

Melt fracture occurs when polymer melt flow transitions from stable shear to stick–slip instability after exceeding a critical shear stress at the die exit.

This disrupts the continuity of the melt layer on the die surface, resulting in sharkskin defects and uneven film morphology.

The risk increases with higher line speed, narrow die gaps, high molecular weight resins, and metallocene-based polyethylenes.

Why are fluoropolymer PPAs being replaced?

Fluoropolymer PPAs function by migrating to the die surface and forming a low-energy lubricating layer that reduces friction and stabilizes melt flow.

However, their environmental persistence as PFAS-related substances is driving regulatory restrictions in the EU, North America, and other regions.

As a result, film producers are shifting toward non-fluorinated processing systems that maintain:

• High line speed stability

• Low haze and high gloss

• Long-term die cleanliness

• Regulatory compliance

How do PFAS-free PPAs eliminate melt fracture?

PFAS-free PPAs reduce melt fracture by modifying the interfacial dynamics between polymer melt and die surface rather than relying on fluorinated surface energy reduction.

They create a controlled molecular lubrication layer through interaction with both the metal interface and the polymer matrix, stabilizing slip conditions during extrusion.

This mechanism suppresses stick–slip instability, reduces shear stress fluctuation, and improves surface uniformity at high throughput.

SILIMER PFAS-free PPA technology for PE Film Extrusion

How SILIMER PFAS-free PPAs work in PE extrusion

SILIKE SILIMER series PFAS-free PPAs are engineered for polyolefin extrusion systems requiring high-speed stability and defect-free film production.

Their performance is based on a multi-segment molecular architecture:

• Polar segments

Interact with metal surfaces (screw, barrel, die) and form a stable interfacial lubrication layer that reduces melt adhesion and suppresses die build-up.

• Polysiloxane backbone

Provides ultra-low friction and high thermal stability, improving melt flow behavior under processing stress.

•Non-polar hydrocarbon chains

Ensure compatibility with PE/PP matrices and enable uniform dispersion and controlled migration during extrusion.

This structure enables the formation of a dynamic, self-renewing lubrication layer that replaces fluoropolymer-based surface modification mechanisms.

What performance benefits do SILIMER PFAS-free PPAs provide?

 Like traditional Fluoropolymer-Based Processing Additives, when applied in LLDPE, HDPE, or mLLDPE extrusion systems, SILIKE SILIMER PFAS-free PPAs as  Fluoropolymer PPA Alternative, deliver:

♦ Elimination of melt fracture and sharkskin defects

♦ Reduced die build-up and improved operational stability

♦ Lower extrusion pressure and improved energy efficiency

♦ Stable optical performance including haze and gloss control

♦ Consistent output in blown, cast, and multilayer film processes

How compatible are PFAS-free PPAs with existing extrusion systems?

SILIMER PFAS-free PPAs are designed as drop-in solutions for existing polyolefin processing lines.

Products such as fluorine-free PPA SILIMER 9100 and PFAS-Free PPA Masterbatch SILIMER 9301 can be directly introduced into compounding or masterbatch systems without equipment modification.

They are compatible with:

♦ LLDPE / HDPE / mLLDPE

♦ Virgin and recycled polyolefins

♦ Blown film, cast film, and multilayer structures

♦ High-speed metallocene PE extrusion systems

How do PFAS-free PPAs support regulatory compliance?

PFAS-free PPAs(eg, SILIMER series products are PFAS-free polymer processing aids, which were researched and developed by Chengdu Silike. These non-fluoropolymer processing Aids eliminate persistent fluorinated substances and support global regulatory transition toward safer polymer processing systems.

They align with:

→ EU Packaging and Packaging Waste Regulation (PPWR)

→ Emerging PFAS restrictions in North America

→ Circular economy and sustainable packaging initiatives

What applications are suitable for SILIKE SILIMER PFAS-free PPAs?

SILIKE SILIMER PFAS-free PPAs are suitable for a wide range of polyolefin processing systems, including:

♦ Blown film extrusion

♦ Cast film production

♦ Multilayer packaging films

♦ Recycled polyolefin processing

♦ High-speed metallocene PE systems

♦ Fiber, monofilament, cable, and pipe extrusion

♦ Masterbatch and compounding systems

Technical summary

PFAS-free PPAs, such as the SILIKE SILIMER series, include fluorine-free additives, fluorine-free masterbatches, pure fluorine-free PPAs, PTFE-free additives, and PFAS-free extrusion processing aids. These  polymer processing lubricants are designed to replace fluoropolymer-based surface modification with a molecular interfacial lubrication mechanism.

Instead of forming a persistent fluorinated coating, they generate a dynamic and reversible slip layer at the die interface, stabilizing melt flow and eliminating surface defects under high shear conditions.

PFAS-Free Processing Aids for Film Extrusion: Frequently Asked Questions（FAQ）

What is a PFAS-free PPA?

A PFAS-free PPA is a non-fluorinated processing additive that reduces melt fracture in polyolefin extrusion by forming a dynamic lubrication layer at the die interface.

Can PFAS-free PPAs match fluoropolymer performance?

Yes. SILIKE SILIMER PFAS-free PPAs deliver comparable performance in melt fracture elimination, die pressure reduction, and optical stability.

Which film types are suitable?

SILIMER PFAS-free PPAs are suitable for LLDPE, HDPE, mLLDPE, blown film, cast film, and multilayer film structures.

What are the environmental benefits?

 SILIKE SILIMER PFAS-free PPAs eliminate persistent fluorinated chemicals, reduce regulatory risk, and support sustainable polymer processing.