Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


silicone use restriction in automotive industries?

silicone use restriction in automotive industries?

silicone use restriction in automotive industries?

Hi everybody,
We have a client who developed a protection device made from soft hypoallergenic material mainly from silicone.
The question is if somebody known some things about restriction for the use of silicone content devices in the automotive industries.
All opinions will be very appreciates.
Best regards,

RE: silicone use restriction in automotive industries?

Silicone, used to be a trademark, but now is a general name for polymers based on polydimethylsiloxane.  Silicone is not listed as a restricted or reportable material by Ford or GM.

RE: silicone use restriction in automotive industries?


I have heard that silicone can cause problems if it comes into proximity of paint plants, leading to a painting defect sometimes referred to in slang as 'fish eyes'.

not sure if this helps !!


RE: silicone use restriction in automotive industries?

If you are referring to commercial silicone products, these compounds have an adverse effect on paint operations. Most OEM's go to great lengths to keep silicone products well isolated from paint operations.

RE: silicone use restriction in automotive industries?

Silicone products as a general rule are banned from OE sites due to the catastrophically negative effects on painting and adhesives bonding.

Having said this, many forms of silicone are non reactive to painted surfaces, and are OK to be used.

If your client's product is to be fitted in trim, it is potentially OK to be used.

Most OE's will require a paint compatibility test to be done on the material - probably both the encapsulating material and the inner material to ensure that any risks are known.

Your first step would be to check this compatibility, and also perhaps the impact on for example glass bonding adhesives.

RE: silicone use restriction in automotive industries?

This probably won't affect you, but there is another area of concern for silicone products: the engine components. Even minute amounts of silicone oils and polymers will burn and produce silica particles, which in turn clog the lambda sensor and shut down catalysts.

In general, there are a few bad low-molecular and very fluid silicone oils which have the tendency over spreading all over the place and contaminating production halls from floor to ceiling. They can disrupt the adhesion of paints, glues or even cause foams to shrink. This is what has made many car manufacturers particularly careful.

But in spite of their undeserved bad reputation, silicones are widely used in the automobile industry - most cars have a few pounds of silicone altogether. The important thing is to make sure that you use a compound with no monomers or volatile components and that your polymer is not reversible, such as LSRs and RTVs (no moisture-cure products!).

Good Luck!

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close