| Author |
Message |
Jeff Williams RA
Senior Member
Username: architectjw
Post Number: 32
Registered: 10-2013
| | Posted on Tuesday, January 22, 2019 - 09:51 am: |    |
Does anyone know the level of incompatibility between silicone and asphaltic resin materials when they are in contact with one another? Does the asphaltic resin material degrade the silicone material? Is it a fast process? |
Brett Scarfino (Unregistered Guest)
Unregistered guest
| | Posted on Wednesday, January 23, 2019 - 09:27 am: | |
What I've encountered in the past is discoloration where joints touch the "asphalt" backing on peel-and-stick products. I've seen sim. discoloration in silicones from setting blocks. No clue how long it took to bleed into the silicone, but guessing it is a slow process.
I would suggest you contact silicone sealant manufacturer. They will (or should) have experience dealing with your specific situation, and/or could provide compatibility testing of the asphalt in combination with their specific sealant. Before I worried about compatibility, I'd want to make sure they adhere to one another (which I presume is important to your situation). |
Colin Gilboy
Senior Member
Username: colin
Post Number: 458
Registered: 09-2005
| | Posted on Thursday, January 24, 2019 - 10:42 am: | |
Asked Momentive to comment on this question:
Yes, a discoloration (in non-black silicones) will occur at the interface of these two materials. It is only on the surface of the silicone rubber (where it can receive UV rays) and does not interfere with the ability of the silicone to perform as intended. It is aesthetic only. If using black-colored silicone sealants and/or coatings, the discoloration may not be evident.
-Errol Bull, GE Silicones
Colin Gilboy
Publisher, 4specs.com
702-505-9119 - Las Vegas
|
Jeff Williams RA
Senior Member
Username: architectjw
Post Number: 33
Registered: 10-2013
| | Posted on Thursday, January 24, 2019 - 01:57 pm: | |
Thank you for the comments. I probably should explain myself a little better. At this point I am not concerned about discoloration. Just deterioration of the material. I am using a pre-compressed foam expansion joint in a 100 year old building. The joint has asphaltic mastic sealant impregnated with asbestos on the sides of the joint that is non friable. (This was a unforeseen condition.) The contractor was claiming that the mastic would deteriorate the silicone face of the expansion joint. The expansion joint material was already purchased so I didn't want to throw it away. The manufacturers rep was stating they would not give me a warranty but didn't have strong language about deterioration of the material. I was able to speak to someone much higher in the chain and they said I could encapsulate the mastic with epoxy and they would honor the warranty. The building will be decommissioned in the next 7 years. I am concerned about longevity but the next owner may make major changes that would negate this issue. I always appreciate the knowledge if get from this forum. |
ken hercenberg
Senior Member
Username: khercenberg
Post Number: 1208
Registered: 12-2006
| | Posted on Thursday, January 24, 2019 - 02:32 pm: | |
So in this case the silicone is a preformed extrusion, not a wet seal product, correct?
Asphalt might break down other components of your seal like the impregnator of your foam or the foam itself. Asphalt likes to chemically react with lots of substances like foam plastics, EPDM, water, etc. Since the foam is presumably your secondary seal, that could be a concern. Silicone likes to stick to things. It gets along with lots of substances. Even surfaces that can discolor silicones, or be discolored by silicones, tend to stick pretty well. |
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