On Fri, 30 Nov 2018 08:01:50 -0800 (PST), wrote:

On Thursday, November 29, 2018 at 9:22:33 PM UTC-8, Jeff Liebermann wrote:
However, carrying such a large can on a ride is probably impractical.
When the same discussion appeared in r.b.t a few years ago, I decided
that quantity might be a suitable substitute for quality. I bought
30x tubes of cheap Chinese glue at a cost of about $0.50 per tube.
https://www.ebay.com/itm/153039763013

That's the stuff used in bike shops and I've never seen them drying
up either. I suspect that the contents are different.

They certainly do dry up eventually. I leave a few tubes in my car in
the automobile tire patch and plug kit. The tubes are larger, but the
contents seems like the same glue and solvent. The tubes dry out
after about a year in hot car. I suspect that the Rema "cold
vulcanizing fluid" type adds some kind of vulcanizing accelerator to
deal with the unvulcanized rubber patch.

One thing I haven't tried is marking the tubes with their measured
weight, to see if I can at least identify which tubes are lacking
contents. Also, I've never seen a dry tube that still has some
residual liquid rubber cement left. It's always good as new, or
containing a small amount of some kind of white powder, and nothing
else. Weird.

"Repair patch for an elastomer component, in particular for a vehicle
tire, having increased adhesive strength"
https://patents.google.com/patent/US20120247648A1/en
See item [0005].

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558