Freudenberg Sealing Technologies
20-close First-Hand News?

Obtain news and background information about sealing technology, get in touch with innovative products – subscribe to the free e-mail newsletter.

Elastomer Materials


“Materials” are the foundation of our technology. Every day, people deal with products that possess seals and they generally know very little about the materials with which they are made. For example, plastic is a comparatively new material and has long been considered to be a “wonder substance”. But why is plastic so flexible and how are the various mixtures differentiated from one another? When is a silicone seal better than one made of polyurethane or rubber?

VMQ FVMQ Rubber Material Properties

VMQ, PVMQ, FVMQ - Structural Formula

Silicone rubbers belong to the category of synthetic polymers in which silicon atoms are linked together with oxygen atoms. They are stable in hot air and ozone, in water, in animal and plant oils, and fats. But they do not stand up to low molecular weight esters¹ and ethers, acids and alkalis, along with aliphatic (such as gasoline, propane and methane) and aromatic hydrocarbons (such as benzene, xylene and tolulene).


Silicone rubber displays high thermal resistance and good cold flexibility from −60 °C to 200 °C, but has little tensile strength, elongation or abrasion resistance. FVMQ withstands even low temperature applications up to -80°C. VMQ silicone elastomers are used in demanding thermal applications, and, due to their purity, are especially suited for hygienic uses in the food and pharmaceutical industries like the VMQ 117055. Due to its very good physiological characteristics, silicone is a proven sealing material, especially for butterflybutterfly valve seals. Their low breakaway torque ensures reliable switching over their entire lifecycle.

Seals made of liquid silicone (LSR) can even adopt the phenomenon of ultrahydrophobicity. Without a coating or a material change, the mold leaves behind a hill and valley structure in the micron range. The friction-reducing seal surface contributes to significantly easier assembly.

¹ Chemical bond that results from an alcohol and an organic (or inorganic) acid subjected to dehydration.

Please enter your email address and password.

Email address*


Password forgotten? Click here to reset.

* mandatory fields

You've logged in successfully.

Register and get instant access to exclusive content.

Please fill in all fields

First Name*

Last Name*

Email address*

Company / Organization*


Please repeat your password*

* mandatory fields

Thank you. Your subscription was successful.

We have sent you an e-mail. Please click on the included activation link to complete the registration.

Click here to continue to login.

Have you forgotten your password?

Please enter your email address to reset it.

Email address*

* mandatory fields

Your password has been successfully reset.

Click here to continue to login.
Big city with skyscrapers

Join Us!

Experience Freudenberg Sealing Technologies, its products and service offerings in text and videos, network with colleagues and stakeholders, and make valuable business contacts.

Connect on LinkedIn! 70-external-link