Non destructive ways to differienciate between Neoprene and EPDM
Non destructive ways to differienciate between Neoprene and EPDM
(OP)
Hi all,
We had a problem with diaphragms for vacuum pumps. It used to be made of Neoprene and all of a sudden the supplier used EPDM. For our application, we really need Neoprene. Since we don't really know when the supplier started to use EPDM, we want to be able to test the diaphragm to identify the material without having to destruct the part. Any easy way?
Thanks
IB
We had a problem with diaphragms for vacuum pumps. It used to be made of Neoprene and all of a sudden the supplier used EPDM. For our application, we really need Neoprene. Since we don't really know when the supplier started to use EPDM, we want to be able to test the diaphragm to identify the material without having to destruct the part. Any easy way?
Thanks
IB





RE: Non destructive ways to differienciate between Neoprene and EPDM
Regards,
Cory
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Non destructive ways to differienciate between Neoprene and EPDM
We are still looking.
IB
RE: Non destructive ways to differienciate between Neoprene and EPDM
If it is a multi cavity mould, make sure you weigh each cavity, as they may vary from cavity to cavity.
Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Non destructive ways to differienciate between Neoprene and EPDM
Thanks for the tip, even though it didn't work. It's very difficult to see the difference between the two parts since they are the same color, same shape and same weight. There is a metal disk inside the part that I think is interfering with the test we try to do.
We keep on looking!
IB
RE: Non destructive ways to differienciate between Neoprene and EPDM
RE: Non destructive ways to differienciate between Neoprene and EPDM
This will be time consuming and probably unreliable, and may also have health issues if done as a process rather than a once off test.
Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Non destructive ways to differienciate between Neoprene and EPDM
RE: Non destructive ways to differienciate between Neoprene and EPDM
RE: Non destructive ways to differienciate between Neoprene and EPDM
We will try to use the petroleum-based products. We will do some tests. We want to be able to use the test on site where technicians will need to change the part.
IB
RE: Non destructive ways to differienciate between Neoprene and EPDM
Iboivin:
The best way to absolutely identify the difference between Neoprene (polychloroprene) and EPDM is by Infrared Spectrophotometry. Infrared analysis yields a “fingerprint” of the chemical composition of the polymer, and can easily differentiate between both polymers.
Most labs can perform infrared analysis. Usually the analysis is somewhat destructive --- a small sample is taken and dissolved or ground up or a thin cross-section taken for the analysis. However, if the part is not too large and has a reasonably flat surface, the lab can perform ATR (Attenuated Total Reflectance). This IR technique will identify what polymer was used to make the diaphragm.
Sounds expensive, but it really isn’t. This equipment is a staple for most labs. An IR spectrum will generally run around $200.
Rich Geoffroy
Polymer Services Group
polyserv@cox.net