Posted by Eins on November 18, 2000 at 11:48:33:
does He react with rubber?
Here's the situation:
You all know that He is used to inflate balloons which then ascend because they are lighter than air. If you keep the (rubber, not aluminum foil) balloon long enough (two, three days), and then re-open the balloon, it will not shrink back to its former small shape but remain close to its maximum sphere shape. This would indicate that the rubber lost its stretch.
An air filled balloon, however, will shrink back close to its former shape.
What this simple experiment tells me is that there seems to be a chemical reaction between the (industry grade) He and the balloon material. Has anyone ever noticed this and does it have any significance for Trimix diving?
Eins