Fluoro-Seal
Home Services Products
Contact
About Us Site Map FAQ More Info Log In
 
 FAQ
 
Fluorination permeation barrier FAQ
 

      Permeation Barrier Treatment

Q. What are the benefits of Barrier Treatment ?

Benefits of Fluoro-Seal Fluorination
Five levels of Fluorination treatment
All sizes of parts and containers treated
All styles and shapes treated
Inside & Outside walls treated (all exposed surfaces)
Reproducible Fluorination results, Consistent Treatment
Applicable to Any Fabrication process including injection, injection blow, stretch blow, roto-molding and thermoforming
Multi-part or Welded Assemblies
All Polyolefin Manufacturers
7-10 Day Lead Times
Multiple locations in USA and Overseas
In-House Operation Available for Large Volume Customers
Licensing Package Available

Q. What problems does the Barrier Treatment address?

A. The Fluoro-Seal Process virtually eliminates or reduces a variety of problems normally associated with the chemical attack of polyolefins including:

Chemical permeation

Paneling and distortion

Product weight loss

Container discoloration

Odor emission

Flavor, fragrance and/or active ingredient loss

Interaction of the container with the product

Fluoro-Seal can reduce chemical permeation for many products up to 1000 times!

Q. What can be treated?

A. Any size or shape container, part or film made of polyolefin plastic from very tiny to 10,000 gallon tanks. In addition to HDPE, LDPE, PP, and UHMW-PE, Fluoro-Seal can fluorinate a variety of other materials (including thermoplastics, rubber and other elastomers and some nonmetallic and metallic solids) to modify their chemical permeation resistance or surface characteristics.

Q. What fluorination level should I use?

A. The level of fluorination that you use is dependent on so many factors it is impossible for us to know how your container will perform with your product. Product formulation, container size and style, resin and additives are some of the factors that impact on the final results. For this reason, Fluoro-Seal always recommends product testing be done with the actual product and exact container and closure system proposed to determine the total package that will meet your requirements. FSI feels this container qualification process is so vital that we are happy to treat a reasonable number of containers at various levels for testing purposes.

Q. How is fluorination performed?

A. Items to be treated are put into a sealed reactor and exposed to a measured amount of elemental fluorine gas under specifically controlled conditions. Having very specific parameters for treatment enables us to reproduce our various levels and treatment options with great accuracy and control.

Q. Can you give me a more technical picture of what fluorination termagant does?

A. Fluorine is chemically bonded to the chain-like molecules on the outermost surfaces of the plastic. The reaction is permanent and forms a thin fluorocarbon polymer surface layer with heightened chemical stability. Once grafted in place, the fluorine is permanent and not readily removable, nor does it become unbound with time. This layer imparts outstanding hydrocarbon solvent barrier and consequently has found growing uses in packaging and other industries.

This barrier greatly reduces the permeation and scalping of a range of fuels, chemicals, solvents, flavors and fragrances. Container softening and/or swelling can be reduced in many cases and long term paneling through weight loss of product can often be brought down to an acceptable level. Fluorination effectively extends the application bounds of polyethylene containers and tankage. This allows inexpensive polyethylene to be used in applications with aggressive chemicals, such as with agricultural chemicals, solvents, institutional/industrial cleaning formulations, food, pharmaceuticals and cosmetics where an untreated container would have marginal success in containing the product.

Q. How long will the treatment last?

A. The fluorination treatment is a permanent molecular bonding of fluorine atoms on the exposed surfaces of the polyolefin substrate.

In all fluorination processes for rigid polyethylene packaging and tankage, fluorine is chemically bonded to the chain-like molecules on the outermost surfaces of the container. The reaction is permanent and forms a thin fluorocarbon polymer surface layer with heightened chemical stability. Once grafted in place, the fluorine is permanent and not readily removable, nor does it become unbound with time.

Excepting surface abrasion and rare cases of extreme reactive agents, the barrier performance resulting from the fluorination treatment lasts the life of the container, even in multi-trip packaging such as oil drums and IBC's. Fluorinated automobile gasoline tanks have been extensively tested and shown to deliver exceptional barrier performance in excess of the ten year minimum life requirement.

Q. How can I tell if a container has been fluorinated?

A. Fluorinated containers are much more water wettable than non-fluorinated. This can be detected by observing water beads or spread of dyne test fluids. Generally it is best to perform any test on the inside surface of the container as wettability and dyne tests cannot readily discriminate between fluorination and flame treatment or corona/arc tunnel surface treatments.

Fluorinated containers generally have a detectable loss of subtle indicators, FTIR testing with a surface reflectance sampling accessory (e.g. Harrick, Pike or ASI) to qualify fluorine IR absorbance bands is the most effective method for determining if a container has been fluorinated.

Q. What is a dyne level test?

A. Dyne level is a measurement of the surface energy of a substrate. Both (PP) and (PE) are low energy plastics. Untreated PP and PE have a low dyne reading (usually 30 to 32 dyne). Using Fluoro-Seal surface modification treatment will raise the surface energy level and allow adhesives to achieve maximum surface adhesion.

Q. What are the dyne levels of surface modified fluorinated surfaces?

A. Our fluorination treatment substantially increases the dyne level of HDPE plastics. In most cases the dyne level observed after surface modified fluorination exceeds that of flame or corona surface treatment. The actual dyne levels range from 55 to over 80 dynes/sq. cm.

Permeation Barrier Treatment

Q. What is the Fluoro-Seal Permeation Barrier Process?

A. The Fluoro-Seal Process is a post-manufacture, computer controlled fluorination treatment, whereby plastics and other materials are introduced to elemental fluorine in a strictly-controlled environment under specific conditions of temperature, pressure and time. This environmentally safe application is a custom process with strict quality controls.

Q. What polyolefin resins fluorinate the best?

A. Natural HDPE resin with low amounts of additives fluorinate best. This means they give good chemical barrier and do not exhibit a tendency toward yellowing.

Q. Can pigmented products be fluorinated?

A. Fluoro-Seal has successfully fluorinated every color imaginable, including some pearlescent pigments. With some colors, there may be slight bleaching, so testing is recommended. The most common color for fluorinated bottles is white.

Optimum barrier is always obtained with natural unpigmented resin. Challenging packaging applications have may choose a dual layer bottle with a natural inside layer and trade dress color
outer layer. This allows higher barrier result than would have been possible with a monolayer pigmented bottle.

Monolayer pigmented bottles will prove satisfactory most of the time. However, the treatment level may have to be higher to match barrier performance of unpigmented resin containers.

We strongly recommend chemical compatibility testing. Testing serves as your principle guide to satisfactory performance.

Q. What causes paneling? Can Fluoro-Seal help eliminate it?

A. Paneling is a direct result of a reduction in volume of the contents of a container. The contents being either the liquid, the headspace gas or both. The absorption of solvent into the container walls where it plasticizes the polymer (HDPE) may further aggravate the paneling problem.

Reduction in volume of liquids is due to absorption and permeation. Plasticisation is due to absorption. Fluorination can reduce or eliminate these factors.

Reduction in the volume of headspace gasses is due to absorption of the gas into the liquid or removal of oxygen through oxidation of the contents. Fluorination can not eliminate this problem, but its effect may be greatly reduced through control of the first two factors.

Q. What are the numbers for permeation rates before and after fluorination?

A. Data does exist for weight loss of pure solvents in fluorinated containers and for many there is a substantial reduction of product loss achieved by fluorination. However, FSI does not advise utilizing this data for package engineering.

Most product formulations are a complex mixture of ingredients. Some ingredients may permeate; some others may not. A permanent may be important to efficacy, or may be an inert filler, extender or carrier.

Permeation rates are significantly altered by the presence of An example from the auto industry is that permeation of petroleum fuel through plastic gasoline tanks is increased by the presence of alcohols in the fuel. Trace quantities of fuel injector cleaner in the fuel mix also impact actual fuel permeation rates.

Thus, it is unreliable to use permeation data for single solvents to predict permeation of complex mixtures. The only valid approach is to perform tests with the actual formulation in each container application.(See also Samples, and Testing Protocol).

 
 

 
 
blank  
blank



stop Chemical Permeation


On Site Surface Modification
Container sources
Qualifying Samples
Trade shows
Quality assurance

281-578-1440

back to top 
 

16360 Park Ten Place, Suite 325  Houston, TX 77084 

 Phone: 281-578-1440  |  Fax: 281-578-3159 |  E-mail:sales@fsicorp.com


© 1999-2007 Fluoro-Seal, International, L.P.  All Rights Reserved  |  Last updated 31-May-2007

The information herein regarding our products and services is believed to be reliable to the best of our knowledge. Fluoro-Seal does not warrant the accuracy and completeness of any such information, whether expressed or implied, including warranties of fitness for a particular purpose. It is the user's or purchaser's responsibility to make their own assessment of the suitability of any product or service for the purpose required. The above supercedes any provision in your company's forms, letters or other documents.