Tel: 01989 567 999



Meadex has over 30 years experience producing Precision Rubber Moulding in the UK. We make precision rubber, silicone and plastic mouldings.

As well as manufacturing rubber mouldings in the UK, we also offer a rubber moulding prototyping service. we are a UK custom rubber mouldings manufacturer who work to our clients exacting specifications using injection and compression methods.

What are Fluoroelastomers?

Fluorocarbon elastomers are specialty polymers that possess excellent resistance to elevated temperatures and aggressive chemical media.

Suppliers strive to continuously improve the polymers currently being marketed and also to develop new polymers to withstand the ever changing chemical environment.

We have witnessed the evolution of this type elastomer from a few grades to three distinct families with over 50 polymer grades. An explanation of the differences in the product lines is shown below.

The Fluorocarbon elastomers consist of three basic polymer families:

1: opolymer of vinylidene fluoride and hexafluoropropylene, commonly referred to as Type A. This family has a fluorine content of approximately 66%.

2: terpolymer of vinylidene fluoride, hexafluoropropylene, and tetrafluoroethylene, with a fluorine content of approximately 68% and is referred to as Type B polymer.

3: tetrapolymer family or Type GF, consisting of vinylidene fluoride, hexafluoropropylene, tetrafluoroethylene and a proprietary cure site monomer that allows the material to be vulcanized with peroxides. This family has a fluorine content of approximately 70%.

Fluorine content is an important consideration in choosing a material to use as a gasket seal, because the higher percentage fluorine polymers have greater resistance to swell and degradation from most fluid exposures. Methyl alcohol (methanol) can be used to illustrate this effect.

By discussing with our customers, exactly what service conditions the fluorocarbon seal will need to resist, we can recommend the best available polymer formulation.

We will also work with our customers to develop custom formulations if necessary.

Why Use Fluorocarbon Seals?

Fluorocarbon elastomers, in general, are resistant to automotive oils and fuels, aircraft jet fuels and lubricants, chlorinated solvents, aromatic solvents, water and salt solutions, aqueous acids and some hydraulic fluids .

They are attacked to varying degrees by strong caustics; polar solvents such as acetone and MEK; ammonia; hydrogen sulphide; high ph amine corrosion inhibitors and red fuming nitric acid.

As previously discussed, some properties such as acid resistance can be enhanced by the choice of polymer type and compounding ingredients.

viton seals

Excellent resistance to high temperatures. Customers often ask, "What is the service life of this seal?" This is a difficult question to answer and depends on a number of factors, such as the type of fluid or chemical it is sealing against; the temperature of the service environment; whether the seal is static or under dynamic flex conditions; the sealing pressures involved; and most importantly- the attention and care given during the installation and flange tightening procedure.

The degree of compression necessary to achieve a leak free seal is dependent on the internal pressure and temperature of the fluid stream; the parallelism of the flange surfaces; the design of the seal area ( machined groove, perimeter backing ring; or smooth flange); and the composition of the flange and piping (metal or resin/fibreglass). For most seal applications, a maximum deflection in the gasket thickness of 25% is recommended.

To discuss your moulding requirements call MRM on +44 (0)1989 567 999 or email