GE Silicone II

[Bart Byers]

A year ago I bought a tube of Silicone II caulk for use with a caulk gun. I found I didn't need it. It sat unopened in my house until a few days ago.

I had a pair of athletic shoes whose heels caved in after three days of walking. The space under the inner sole was mostly voids. I figured I could fix the shoes by filling the voids with Silicone.

Apparently the Silicone had gone bad. It took a lot of pressure to pump it out of the tube, and in three days it hasn't cured.

Is that a common problem? Is there anything I can do to cure it?

The tube says GE will replace the Silicone if I send them the tube and proof of purchase. That sounds like more trouble than it's worth.

[Mikey S.]

I don't know how common it is but I had the same experience, I bought 3 tubes of the same GE Silicone II , used 2 and saved one of them about a year. It was hard to get out of the tube, lumpy, and never cured, I finally gave up after a week, scraped it off the door frame I had caulked, washed it with solvent, and recaulked with new caulking.

[MLD]

Will you be surprised to learn that tubes have "used by date" on them. I had a similar problem and noticed the 'use by date ' and it was months beyond it. Returned the tube and got another that had more than a year(s) left on it--I think I got it at Home Depot. MLD

[Frank]

Silicone cures by elimination of acetic acid. Think some moisture is necessary but if it got wet and acetic did not evaporate, this may be source of curing problem. I had an old tube of their Silicone I and in spite of careful sealing (Saran and aluminum foil) tip had hardened but rest was still good. Part of problem is that sealant is in plastic tubes and these tubes are not completely impermiable like glass or metal. Frank

[Charlie Morgan]

Marine versions of silicone sealant do not contain acetic acid, as it might damage or weaken metallic hardware or parts.

CWM

[Bart Byers]

RTV Silicone released a vinegar odor. My only problem with it was like yours: when stored after it was opened, it would cure from the tip down. I could salvage a lot by drilling out the cured caulk.

Silicone II smells like candy and releases ammonia and I think methanol.

[Bart Byers]

Thanks, I went to the kitchen to check just as my supper was about to boil over. It says 9/06.

[Harry]

=EF=BB=BFHello,

Patience is a virtue. It will probably take years for it to "dry" under the circumstance > A year ago I bought a tube of Silicone II caulk for use with a caulk

[Frank]

Interesting. Must be different curing chemistry involving different end groups. I cannot readily Google up but op's note would indicate that if polymerization does not complete, you end up with viscous silicone oil.

[mm]

What solvent do you use for that stuff? Nothing seemed right to me.

I too have had old GE silicone that wouldn't harden. When I'm careful, some glues seem to keep 10 or 20 years before use, but this doesn't seem to be one of them, except see next paragraph.

Although last week, I opened a 3 oz. or so tube of stuff that looked the same, a clear RTV Silicone Sealant Addhesive and Gasketing, that was still good, excellent, after maybe 5 or 10 years in an unheated, uncooled ministorage locker. This tube still had the metal seal at the bottom of its metal 'nozzle?'.

Is RTV in general the same thing as GE silicone?

So I wouldn't throw any of this stuff away just because it's old, without trying it first.

I also acquired 2 more tubes of clear and 5 caulking tubes of white silicone, and I hope it is still good too^^. This came from the ministorage my friend runs, and the burglar alarm company owner retired maybe 5 years ago or even ten years, put this stuff in storage, then died a few months ago and his children all took what they wanted, and left a lot of stuff behind.

I sold, for 1 to 3 dollars an item, and otherwise dispersed the burglar alarm stuff at a hamfest, and

^^I also found black silicone for sale at Advance Auto, by Permatex. I should have looked there in the first place it seems.

[Mikey S.]

I cleaned it off with some mineral spirits, it slowly dissolved the gooey mess left after I scraped off the silicone II, without ruining the vinyl frame on the brand new $700 Anderson sliding door I had just installed. Stronger solvents might have damaged the plastic..that was a major concern in this case.

[mm]

Glad your new door came out all right!

Thanks. Mineral spirits. I'll bear that in mind. The silicone stuff is great when it works, but when it won't harden, it's sort of disgusting. Come to think of it, standard Western Electric phones used by phone companies for decades had all the small parts in a metal case surrounded in some sort of clear silicone-like stuff. It kept the phones break-proof I vaguely thing it was gooey, but maybe not hard.