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More Silicone Curing Tidbits
By:mike allen ---}
Date: 4/18/2000, 11:46 am
In Response To: Silicone Cures w/ Airborne Moisture (mike allen ---})

: > wrap and put the hatch in place. The silicone hadn't even started to
: firm
: > up this morning. It appears that without much exposure to the air it
: stays
: > wet. Any ideas? It has been in a 65 degree environment. It is supposed
: to
: > firm up overnight and be ready for exposure to water in 24 hours.

: Looking up several data sheets for diff silicones for full cure - they
: require 3-5 days @ 73deg F AND 50% R.H. (for 1/4in)

: Most say that 'cures when exposed to moisture present in air'. Don't know if
: water only would provide cure, but would assume some part(continuous) of
: the edge must not be covered up so moisture in air can contact. Logical to
: me that if have a 3/4in wide gasket w/ only about 1/16in showing, it might
: take longer that say 1/2in wide by 1/4in thick.

: -mick

Talked to a silicone rep the yesterday:

The molecular moisture(actually 0H ions) in the air catalyzes the polymerization reaction ( of silicone oils ).

But the bottom line is that the curing process can be stopped only if no air is present like in a vaccuum. Even if the 'gasket' is say 3/4in wide and only 1/16in thick or less and closed on one side by say wax, the process is ONLY slowed. It will still cure.

-mick

Messages In This Thread

Silicone, Epoxy, and Plastic Wrap
Mike Hanks -- 4/13/2000, 4:02 pm
Re: Silicone Shrinkage
Mike Hanks -- 4/14/2000, 11:13 pm
Re: Silicone cures with water moisture
Dave Houser -- 4/14/2000, 9:52 pm
Silicone Cures w/ Airborne Moisture
mike allen ---} -- 4/14/2000, 2:13 pm
More Silicone Curing Tidbits
mike allen ---} -- 4/18/2000, 11:46 am
Re: Silicone cures slooowwwly with Plastic Wrap
Mike Hanks -- 4/14/2000, 10:49 am
Re: Silicone, Epoxy, and Plastic Wrap
Nolan -- 4/14/2000, 7:14 am
What cures silicon?
Bruce -- 4/14/2000, 10:14 am
Re: Silicone, Epoxy, and Plastic Wrap
Kent Leboutillier -- 4/13/2000, 6:18 pm
Re: Silicone, Air, and Plastic Wrap
Shawn B -- 4/13/2000, 5:32 pm