• Increase font size
  • Default font size
  • Decrease font size

News Flash

NIST develops greener solution to challenge commercial fire retardants

Stratasys touts World’s first color multi-material 3D printer for rubber & plastics products

Plastrec, a Quebec recycler unveils recycled PET production combining two plastics technologies

Innovations in design come from plastics to win several 2009 International Design Excellence Awards

Polymers can be used to package insulin into a pill for diabetes treatment reports Indian scientists

Researchers develop unique printable thin film supercapacitor using SWCNT

Polymers help Addidas to launch lightest soccer boots and 2010 FIFA World cup match ball never seen before in the field

Princeton university researchers embedded piezoelectric material onto polymer as energy harvester

Researchers show stretchy battery for flexible and stretchable electronics

Are you an injection moulder, you may want to read the ultimate in mould cooling article

Japanese scientists report a unique, smart and self-healing polymer nanocomposite hydrogels

Practical Devices provide useful power from the body

Alberta scientists help to make Canada’s first bio-composite based electric vehicle body design

Can polymer reinforced aerogel make a space mission? University of Akron researchers think so!

A novel technique to manufacture continuous twisted yarn from aligned PAN nanofibers

University of Texas at Austin researchers show use of polymer membranes for fracking in shale gas

Arkema unveils a range of "green" polymers for its textile market

3D systems introduces non-halogenated flame retardant for aircraft applications

Korean scientists provide a different twist to the “Smart Window” technology

Work of North Carolina State Univ. researchers shows how to remove radioactive elements from drinking water

Oil-SAP, a novel development to clean-up oil spill & recovery from Penn State University, USA

It is time to make “Perfect Plastic” reports UK researchers

Kyoto researchers are upbeat about cellulose nanofibers based composites for auto parts

Harvard University researchers design stretchable, transparent ionic conductors

Current trends and future prospects for flame retardants in polymeric materials

Polymer bank notes on the rise to avoid counterfeit paper currencies

Japanese researchers are developing stereo-block type PLAs for high performance materials

Harvard Univ researchers show how soft robotics could navigate a difficult obstacle

Are you interested in self-healing polymers – must read reviews

A new microcellular injection molding process for polycarbonate using water

GM recycles oil soaked booms from the Gulf of Mexico for its Chevrolet Volt under hood parts

Umass, Amherst researchers find ways to hold 300 kilograms of weight using sticky tape

Can polymer reinforced aerogel make a space mission? University of Akron researchers think so!

Mannigton converts large stickers from 2010 winter games into commercial flooring

Using biodegradable polymer, University of Basque country researcher report on bone regeneration

How Collagen nanofibers could find use in Tissue Engineering

A review on polymer/bioactive glass nanocomposites provides current trends in polymer research

Plastic Logic sees mass production of flexible display in 2008

Singapore researchers touts corn starch can help solve body armour and protective sports padding

Something old... Something new.... produces an interesting marriage

Carbon3D, a Canadian company unveils a breakthrough technology for layerless 3D printing

AMI unveils the North American Bioplastics technology agenda

Work of North Carolina State Univ. researchers shows how to remove radioactive elements from drinking water

Can you 3D print yourself? TwinKinds of Germany shows just that!

Can you “Cool Your Roof” - reports researchers from Chinese Academy of Sciences, Beijing

Block copolymers could create hard disks with 10 tera-bit-per-Square-inch:Researchers predict

Austrian researcher reports new opportunities from Silicon oxide Nanofilms

UC Berkley researchers have developed paper thin e-skin that responds to touch

Will your windows generate power one day?

Scientists from Sweden and USA showed electronics can truly be organic or say truly be plastics

Yale scientists develop high performance thin film composite membrane

USA researchers develop all-polymer multilayer coating to retard fire and to suppress smoke

Bio-succinic acid is becoming new green platform chemical for plastics

MIT researchers develop first Solar Thermal Fuel storage platform in solid-state

US and South Korean researchers develop a printing technique to make high performance CNT transistors

Battelle researchers are improving PLA for injection molding applications

Plastics help design non-shatter pint glass to prevent pub attacks

Siver nanowire electrodes for flexible electronics

Swedish researchers show highest reported charge capacities for all polymer paper-based battery

In Milan, art and science get together to showcase Vegetal, weather resistant designer chair

ZogglesTM earns Invention of the year 2010 award and keeps the fog away

Researchers review how to characterize polymer nanocomposites by different microscopicy techniques

Sabic Innovative Plastics unveils its newly developed a clear flame retardant Polycarbonate copolymer

Electric Glue: Another twist to make controlled polymer-surface adhesion

Austrian scientists claim to be the first to have developed an image sensor that is fully transparent

Stanford university researchers detect mercury ions in sea water using organic polymer transistor sensor

Can Gas Jet process challenge electrospinning in producing polymeric nanofibers?

For the first time, IBM researchers showed 3D molecular structure could be observed

Stanford researchers use cheap plastics film to make safe lithium batteries

Prof. Alan Heegers group demonstrated the potential of plastics solar cells

MIT team aims to develop application specific surgical adhesives to seal tissues

Green Composites - all you wanted to know about

Rutgers Univ researchers moves plastic electronics with graphene based PS thin films

Advanced nanocomposite membrane technology of NanoH2O turns it to a Global clean technology company

MIT researchers show how to draw Polyethylene as nanofibers and get a very high thermal conductivity

If you follow plastics electronics - follow Unidym’s innovative product lines

Caltech researchers show through telechelic polymers how to produce a safer and a cleaner fuel

Current status in graphene based polymer nanocomposites – a review

Scientists from IBM and Stanford University are developing new plastics recycling process

Can polycarbonate be replaced with another polymer? Click chemistry might provide the answer!

IKV researchers report thermoplastic/metal hybrid materials for Direct manufacturing electronic part

James Cropper Speciality Paper touts recycling of disposable coffee cups

How computer modelling & 3D printing create fracture resistant composites – reports Stratasys and MIT researchers

Braskem S.A. is leading the way to manufacture biobased polyethylene using catalytic dehydration

Stanford Univ researchers make Jell-O-like conducting polymer hydrogels

New ambipolar polymer beats others: reports US researchers

How plastics helping revolutionize stretchable electronics applications – a review, not to be missed!

USA researchers report polymeric blood-resistant surgical glue that can repair minimally invasive heart defects

Chinese researchers made a bendy polymer that could separate aromatics hydrocarbons from aliphatic

Non-toxic, liquid bandage from Chesson Labs of Durham, NC is ready for the healthcare market

Wax could be green too – touts GreenMantra Technolgies!

Teijin Techno Products claims to be world’s first mass producer of aramid nanofibers

French scientists tout first use of nano-structured assemblies that could revolutionize dentistry

Nanoparticle coating prevents ice build up

Cima NanoTech flexes mussels with its non-Indium Tin Oxide, high performance transparent conductors

UCLA scientists showed how simple it could be to make conducting polymer thin films

Binder free multilayer graphene based polymer composite for high performance supercapacitor electrodes

US researchers develop shape memory polymer nanocomposites exhibiting fast actuation speed

Can you “Cool Your Roof” - reports researchers from Chinese Academy of Sciences, Beijing

Canadian researchers claim world’s most efficient “inverted” OPV solar cells

MIT researchers develop first Solar Thermal Fuel storage platform in solid-state

Strain Paint: an alternative to strain gauges

McMaster university (Canada) researchers developed flexible solar cell technology

Researchers gather to discuss advances in organic photovoltaics (OPV)

German researchers unveiled a green approach to electrospinning technique for making biodegradable nanofibres

Brazilian scientists are actively pursuing bioplastics research and innovation

Univ of Texas @ Austin scientists reported method to produce a large scale reduced graphene oxide

How blood can clot to heal a wound - Science reports

Norner touts major research project on polymers based on carbon dioxide

Self-healing plastics healing like human skin

Polymer helps to designing higher capacity Li-ion battery

Rice Univ (USA) researchers grew high quality graphene from polystyrene, cookies, grass, cockroach leg & dog feces

Bayer uses PC film Makrofol? for it's new Innosec Fusion? technology to stop counterfeiting

A team of researchers demonstrate plastics and graphene can work together to make touch screen device a reality

World’s first all-plastic LED lamp comes from Japan

Fluorinated Polymer Processing Aids: How a laboratory cleanout mistake created a family of polymers that is still growing even after 50 years

E-mail Print PDF

Mistakes in science often lead to inventions. Polymer science is no exception. Around 1961, a laboratory scientist processing fluoroelastomers and polyolefins on the same extrusion line, discovered that for some reason he was able to process the most difficult polyolefins obtaining good appearance at higher throughput rates.  An important patent was granted as a result of this work; the patent claimed the addition of small amounts of fluoropolymers (0.1 – 2.0 wt %) to polyolefins gave amazing processing benefits [1]. This is how fluoropolymers and fluoroelastomers gained their fame as polymer processing aids (PPA).

The beginning – Goodbye to melt fracture

After the patent rights expired around 19841, a flood of activity centered around this modification to polyolefin processing.  The early focus was on Linear Low Density Polyethylene (LLDPE) blown films and high-speed wire & cable extrusion.   This is a result of the well-known challenges to process LLDPE. At that time, several polymer manufacturers, high-end compounders and film processors began contacting suppliers of fluoroelastomers made from vinylidene fluoride (VF2) and hexafluoropropylene (HFP).  They began creating high quality low density polyethylene products at up to triple previous production rates on extrusion machines that had previously been only used to process LLDPE using narrow die gaps.

figure_1_split screen_photo1 

Figure 1:  Split screen photo of hexene-based LLDPE plus masterbatch containing 1% of Kynar Flex® 2821 PPA: left side before adding the PPA and right side almost immediately after adding the PPA

A split screen photograph taken in 1987 (Figure 1), shows the immediate effects of adding a fluorinated PPA to a LLDPE blown film, which has been running for 40 minutes full of melt fracture.  It cleared up in less than 4 minutes after the addition of a 1% masterbatch of LLDPE + Kynar Flex® 2821-00.  With such dramatic improvements, it is understandable why polyethylene extrusion and polyolefin resin manufacturers and compounders got excited.

These benefits resulted in a flurry of research on fluoropolymer PPAs that produced rapid results.   Fluorinated resin manufacturers were exploring new monomers, varying VF2 and HFP ratios, varying molecular weights, changing levels of PPA addition, studying the effects of particle size, investigating the importance of particle distribution, and analyzing the effects of processing temperature while using fluorinated PPAs.

The next important patented breakthrough resulted from the study of interactions of common polyolefin additives in blends with PPA. Researchers found that polyethylene glycol had a synergistic effect on the performance of the PPA.  It helped to reduce the levels of PPA required to minimize sharkskin defects, torque, gauge control, processing temperatures and pressure, while increasing processing throughput, and film transparency2.

During the same year, the Kynar® PVDF PPA team at Pennwalt (now Arkema) commissioned a blown film extruder. The technical staff of the supplier stated that based on existing knowledge it would be impossible to run LLDPE on a 2.5”, 30/1 LD extruder with a 10” diameter die and a 0.025” die gap.  Figure 2 shows the actual reduction trend of pressure versus temperature in the virgin hexene-based LLDPE having less than 1 MI (Melt Index) with the same resin with and without 1% Kynar Flex® 2821 masterbatch.  The masterbatch compound contained a let down ratio of 22:1 into the host resin resulting in 450 ppm concentration of Fluorinated PPA.  The results were outstanding but typical of the results that film processors were obtaining in the 1980s.  It is interesting to observe that the pressure reduction shift is almost a parallel line with 800 – 1200 PSI pressure reduction regardless of the melt temperature of the extrusion.

figure_2_extruder pressure comparison1

Figure 2:  Extruder Pressure Comparison of Virgin LLDPE and LLDPE with 450 PPM Fluorinated PPA at a range of Melt Temperature

In the same study, the output of clear film without sharkskin (surface melt fracture) had more than tripled (i.e. from 66 pounds per hour to 204 pounds per hour) at the same melt temperature. Output was limited by the equipment’s throughput since screw speed could only be increased from 34 RPM to 102 RPM (see Table 1).

table1_ppa data table revised 

Table 1:  Processing Parameters Comparison of LLDPE Control vs. LLDPE with 450 ppm of Fluorinated PPA

Figure 2 and Table 1 show how fluorinated PPAs bring large benefits to LLDPE processors through benefits that include equipment longevity, production capacity improvement, higher strength, improved appearance, and reduced scrap. In addition, these additives enabled the use of existing equipment to be used to manufacture products made from more than one version of a polymer.  Figure 3 gives an example of a microscopic view of a PE film with a visible melt fracture that was processed without a fluorinated PPA and a comparison with the same PE resin extruded with just 300 ppm of fluorinated PPA.

As the industry soared along with this technology, manufacturers with less obvious issues began considering that fluorinated PPAs could have incremental benefits that would differentiate them from their competitors.  Compounders started to supply PPA compounds for extruding LDPE, HDPE, UHMW-PE and Cross-linked polyethylene (PEX) that could improve the appearance of marginally smooth products.  Injection and blow molders could fill molds by up to 8% more easily, without going to a higher melt flow rate resin with lower performance properties.  In all types of processing, other processing aids like stearates that were affected by chemicals and sunlight could be replaced by fluorinated PPAs, thus reducing longer-term exposure problems of the polymer.   The use of fluorinated PPAs has been extended to applications with Polypropylene, Polyurethane, and PVC in addition to the various polyethylene resins.

 figure_3_under microscope_left1   figure_3_view under microscope right1

Figure 3:  Microscopic comparison of extruded metallocene PE film before (left) and after addition of 300 ppm of Kynar® 5300 PPA (right)


Continued Development

Fluoropolymer producers have made great efforts to focus on the form of the additives to allow good mixing with any synergists to obtain the best mixing and proper dispersion of the small amounts of PPA to gain the desired effects.  The dispersion of PPA in the polymer matrix is critically important and should be considered carefully.  Much has been written on combining the concentrates and the fluorinated PPA. There are many patents in this area; one important patent is US 8053502 B23 which reports that PPA reduces or eliminates extrusion defects without causing deterioration in the yellowing index of the extruded resin.  If the polymer or the master batch containing the PPA does not match up well with the melt flow rate of the host polyolefin, the PPA can lose its ability to coat the die and aid in the reduction of melt fracture.  In other words, the PPA can add to the problem. Studies have shown that surface melt fracture is a die exit phenomenon4. It has been reported5 that visualizing polymer/die interfaces in high resolution images of PPA/PE blends can show that PPA coating occurred in 3 stages.


The Future - Can PPA help in reducing die build-up?

Die build up is the newest phenomenon that fluorinated PPAs are helping to avoid.  Companies extruding pipes and profiles with relatively slow extrusion speeds normally would not see any production speed benefit or increased product gloss by using a fluorinated PPA, yet they are now turning to these additives to reduce unwanted buildup on the die that can compromise the integrity of the final product.  Die buildup can do more than create unsightly residue on the extrusion. It can attach to the product and generate a weak point. It can accumulate and degrade at the die creating safety issues.  Die build up can be an acute problem in products containing high levels of fillers and additives.  

Research is continuing on fluorinated PPAs to address the concern that die build up adds to the complexity of the process.  Processors still want good film, wire, or pipe with lower stresses on their extruder, but also, they want to avoid the negative effects of die build up.  PPAs that work best for processing effects may not be optimal for reduction of die build up, and some PPAs that may reduce die build up well may not be very effective in reducing melt fracture.  As a result, this has become a major area of study in 2018, leading to the introduction of newer grades of fluorinated PPA materials. These are designed with specific melting points, molecular weights, and ratios of co-monomer, and VF2-based polymers rather than elastomers.  Figures 4 & 5 show examples of die build up from a capillary and tube extrusion without PPA and Figure 6 shows a comparative reduction over time of die build up with the use of a specific fluorinated PPA.

 figure_4                                                                                                    figure_5

Figure 4:  Example of die build up in highly filled Polyethylene                                                                                                                        Figure 5:  Common problem of die build up in tubing extrusion

                                                                                       figure_ 6 split screen of die build up left                                            figure_6 split screen of die build up right

Figure 6:  Die build up in a capillary of highly calcium carbonate filled PE without PPA (left) and 30 minutes after the introduction of 1260 ppm of Kynar® 705 PPA (right)


Die build up is caused by many variables such as concentration and weight of additives, temperature of extrusion, rate of extrusion, molecular weight of the host resin, and design of the dies. The selection of the loading of the fluorinated PPA becomes even more critical to the elimination of melt fracture.  Too much PPA may add to die build up, and not enough PPA may mean the effect is severely restricted by the other components in the compound.  Additionally, if the choice of molecular weight of the fluorinated PPA is not made very carefully,  too much PPA can pass through the process without getting to the die wall in time to compete with the other additives in the stream.  It is common to add as much as 1200 ppm of fluorinated PPA to reduce the die build up. In contrast, some processors have eliminated melt fracture and improved pressure reduction in the melt with levels as low as 150-400 ppm.


Since the idea of fluorinated PPAs used in polyolefins was accidentally discovered in 1961 and was used by one company for about the next 23 years, the market for these products is now in the thousands of tons globally.  Today, the breadth of its use is commonly presented at conferences on every continent.  What started out as a dramatic processing improvement additive for one polymer (LLDPE), has emerged as a standard processing additive for countless others.  The current trend is for continued incremental improvements in either the processing, appearance or performance properties of the final polyolefin product in injection molding, blow molding, extrusion, and casting.



1. Blatz, P.S., US Patent 3,125,547 (March 17, 1964)
2. Duchesne, D., Johnson, B. V., US Patent 4,855,360 (August 8, 1989)
3. Bonnet, A., Laffargue, J., Triballier, K., Beaume, F., US Patent 8053502 B2 (November 8, 2011)
4. Cogswell, F.N. ; J. Non-Newtonian Fluid Mech. 2, pp. 37-47, 1977
5. Meillon, M.G., Morgan, D., Bigio, D., Migler, K., ANTEC Proceedings, PP. 96-100, 2005



David A. Seiler received his B.S. in Chemical Engineering from Penn State University in 1983.  He is employed for Arkema Inc as the Americas Business Manager Industrial / Global Manager Polymer Processing Aids, and has worked in the area of Fluoropolymers for 34 years. 

Jason Pomante graduated from Lafayette College in 2002 with a B.S. in Chemical Engineering and MBA from Saint Joseph’s University in 2010.  Jason has worked at Arkema for 15 years and is currently the North American Market Manager in the Technical Polymers Division.

Robert Lowrie graduated in May of 2017 with a B.S. in Chemical Engineering from Villanova University. He is currently a Technical Marketing Specialist for Arkema Inc. in the Technical Polymers Division.

david a. seiler                 jason pomante            robert lowrie 

                   David A. Seiler                                                                          Jason Pomante                                                                                     Robert Lowrie