37-ecat E-Catalog
80-services Services
39-magazine Magazine
36-downloads Downloads
35-contact Contact
47-chevron-right
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.

Benchmark For New Elastomer Compounds

Weinheim, July 10, 2023. Freudenberg’s new development for the vulcanization of chloroprene rubber eliminates the need for ethylene thiourea (ETU) as an accelerator – while still meeting the strict requirements of the automotive industry. With this innovation, the company follows its own sustainability goals and also sets a benchmark for new elastomer compounds.

Using ethylene thiourea (ETU) as an accelerator in the vulcanization of chloroprene rubber is standard in the industry. Products with this accelerator have been used successfully for decades and show very good values in terms of low-temperature flexibility as well as the required resistance to media such as greases and lubricants. Due to the risk of reproductive toxicity and its damaging effect on fruit, however, ethylene thiourea should no longer be used if its omission is technically and economically feasible. But so far there have been no alternatives that offer a similar performance or even met the requirements.

That is why Freudenberg Sealing Technologies has developed new elastomer compounds that require no ethylene thiourea accelerator in the manufacture of products made of chloroprene rubber. One of the company’s already successful applications of ETU-free products in the automotive sector is in sealing bellows for joint seals in tie rods, control arms and wishbones. They protect the moving parts from external influences and the leakage of lubricants. When it comes to the development of new, ETU-free elastomer compounds, Freudenberg Sealing Technologies is one of the pioneers and is currently considered a benchmark in this area.

New material compound meets different requirements

For the specialists at Freudenberg Sealing Technologies, the challenge lay not only in eliminating ETU and other harmful accelerators, such as the additional use of tetramethylthiuram disulfide (TMTD), but also in reconciling this with the increased requirements placed on new compounds. In addition to the most efficient vulcanization possible, these include three key requirements that influence each other: significant low-temperature flexibility after targeted aging, compatibility with greases and lubricating additives in direct contact with the sealing bellows, and resistance to hydrolysis. Another goal was to bring the compound optimization into conformity with current and future customer requirements. The specialists at Freudenberg Sealing Technologies succeeded in launching new compounds into series production.

In addition to the statistical design of experiments (DOE), failure analysis, and optimization of mixing processes, the methods used in the compound development included thermal analyses such as differential scanning calorimetry (DSC). This is used to determine key parameters such as the melting and crystallization temperature, relaxation, glass transition temperature, degree of vulcanization, and more. The measurements have shown that one of the most important requirements, for example – behavior in the low temperature range – is being met extremely well. This is also confirmed by feedback from customers in the automotive sector that are already using ETU-free sealing bellows for joint seals in tie rods, control arms and wishbones. They confirm that the new material has much more stable values at low temperatures than other products on the market – which is a significant benefit when used continuously. After artificial aging in water and relevant greases, other parameters such as tensile strength and elongation at break are also within the requirement specifications. This was verified after the corresponding preconditioning with 7 days at 70 °C (158 °F) in grease, 10 days at 80 °C (176 °F) in water and 48 hours in 70 °C (158 °F) hot air.

Figure: DSC measurement in the network diagram (e.g. glass transition temperature Tg at different types of conditioning – in each case, conditioning 7 days with the corresponding storage condition for grease and warm air)

Reducing administrative work

Substituting the harmful accelerator ethylene thiourea in the cross-linking of chloroprene rubber is only one benefit offered by the new elastomer compound. Another advantage is the considerable reduction in administrative work. Since the beginning of 2021, a reporting obligation in the SCIP database of the European Chemicals Agency ECHA has been in effect for all products containing specific quantities of Substances of Very High Concern (SVHC). This applies to the entire supply chain from the manufacturer to the end customer, which makes it very complex. Thanks to the new development, the additional reporting requirement is eliminated, and the reporting can be carried out as before via the existing and globally standardized exchange and management system IMDS.

Ulrike Reich

Head of Media Relations & Internal Communications

Telephone: + 49 (0) 6201 960 5713

ulrike.reich@fst.com 32-caret

Cheryl Eberwein

Director, Corporate Communications

Telephone: +1 734 354 5373

cheryl.eberwein@fnst.com 32-caret

News Service

You can subscribe to the Freudenberg Sealing Technologies news alert service, bringing you the news as soon as they are published. You can always unsubscribe from this service.

Subscribe now! 32-caret

Login with your access data

* mandatory field

Forgot your password? Click here to reset.

Or

Don’t have an account yet? Register now!

You've logged in successfully.

Register and get access to exclusive content

Your benefits

  • Download exclusive documents such as Solution Sheets
  • Live Webinare/On-Demand Recordings on the beverage and food industry
  • Virtual tours of production facilities
  • Resistance tools for selecting the right material

Security Level

* mandatory field

Or

Do you already have an account? Continue to Login.

Thank you. Your subscription was successful.

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

We have sent you an email. Please click on the included link to assign a new password.

Have you forgotten your password?

Please enter your email address to reset it.

* mandatory field

The form has been successfully sent.

We have sent you an email. Please click on the included link to assign a new password.

Further Articles With These Taggings

Overcoming Seal Failures With Freudenberg EPDM 291 Material

21.02.2024

How a major US manufacturer in the health and well-being industry used Freudenberg EPDM 291 material to solve their sealing failures while delivering considerable cost-saving.

Read more 32-caret

Pharmaceutical Food and Beverage Material Expertise

Running On 100 Percent Green Power

15.02.2024

Freudenberg Sealing Technologies is inaugurating a new green plant in Parets del Vallès, Spain.

Read more 32-caret

Automotive Sustainability

A Very Hot Item: Thermoplastics For Up To 1,200 Degrees Celsius

17.01.2024

Freudenberg Sealing Technologies develops extremely temperature-resistant plastics for electric cars.

Read more 32-caret

Automotive E-Mobility Material Expertise

Simriz® – Quick Tooling Ensures a Reliable Supply of FFKM Seals

08.01.2024

Discover how our Simriz® quick tooling & reliable supply chain ensure that an American seed and agricultural chemical company has a reliable supply of FFKM seals.

Read more 32-caret

Agriculture Food and Beverage Material Expertise

Don’t Let Flavor Retention Cost You Money

19.12.2023

Downtime due to transfer retention can be costly, see how Fluoroprene XP saved a manufacturer almost 50% less downtime.

Read more 32-caret

Material Expertise

Long Live The Battery!

06.12.2023

Freudenberg Sealing Technologies produces one million foldable gaskets in Langres, France.

Read more 32-caret

Automotive E-Mobility

Solving Real Customer Problems Every Day

30.11.2023

Freudenberg Sealing Technologies works with some of the industry's best partners to solve real-world problems for end users every day.

Read more 32-caret

Material Expertise

A Fast, Superior Material Solution

07.11.2023

Simriz® FFKM from Freudenberg Sealing Technologies sees strong growth in demand.

Read more 32-caret

Material Expertise Aerospace Agriculture Fluid Handling Construction

Material Development: Boosting Wind Power

26.10.2023

Discover our new EPDM material for buoyancy modules in floating wind turbines. The material features excellent pressure and temperature resistance along with high durability.

Read more 32-caret

Energy Transition Material Expertise Energy Generation
Press Subscription Service

News Service

You can subscribe to the Freudenberg Sealing Technologies news alert service, bringing you the news as soon as they are published. You can always unsubscribe from this service.

Subscribe now!