INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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!

*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.

Jobs

How to improve silicone rubber parts compression set?

How to improve silicone rubber parts compression set?

(OP)

Dear friends kindly let me know how can I improve silicone rubber parts compression set?.

RE: How to improve silicone rubber parts compression set?

Extended post cure and a higher crosslink density will probably first come to mind. Silicone type/grade and filler type/loading may also be influential. But set cannot be regarded in isolation. Other properties and the test environment have to be considered. More info would help.

RE: How to improve silicone rubber parts compression set?

(OP)
Dear Stancom

Thank you very much for your helpful guidance, our formulation is for extrusion as bellow items:

1-Silicone gum rubber-----------150.00k
2-precipitate silica------------105.00k
3-Hydroxyl oil(silicone oil)------6.50k
4-Stearic acid -------------------0.60k
5-Aerosil 200(fumed silica)-------2.00k

TOTAL----------------------------264.100K
Catalyst is 2,4 Dichlorobenzoyl peroxide--1.5 %
If I need to change or replace any item please let me know.
Thanks

RE: How to improve silicone rubber parts compression set?

It is a heavily loaded material so its elastic properties are compromised anyway , but I think the addition of an acid acceptor like MgO (1.5phr) should help improve the efficiency of the Peroxide

Johnnymat

RE: How to improve silicone rubber parts compression set?

(OP)
Dear Johnnymat, thank you very much, heavy loaded is for high voltage resistance. so,please let me know either ATH or MgO is more suitable to achieve both high voltage and compression set?

RE: How to improve silicone rubber parts compression set?

I agree with Jonnymat. An acid acceptor would be useful, although a decent post cure should also get rid of acidic by-products. If for some reason post cure is not carried out, do ensure the cure time is equivalent to at least five half lives.

Curative absorption by silica may not be as pronounced as it can be in sulphur cured rubbers but adding triethanolamine or a more advanced silane agent may be worth trying. Cannot really appreciate why there is a very small level of fumed silica in addition to the main pptd type.

RE: How to improve silicone rubber parts compression set?

(OP)
Thank you very much Stancom,Fumed silica is effective tensile strength,high voltage resistance, hardness and more transparency in silicone rubber.but because of the total cost there is limitation in use.

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!


Resources


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