Synthetic Blubber

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The point is that this technology would allow a thinner wetsuit to provide the same level of protection as a thicker normal wetsuit. So, perhaps you can get the same level of protection out of a noble gas infused 3mm wetsuit as you currently get from a 7mm wetsuit, with the advantage of significantly improved mobility and lower complexity...not to mention the fact that your suit would have less inherent surface buoyancy (due to the denser gas), which means you don't have to carry as much weight, or add as much air to your wing at depth to compensate.
I see, thanks for the explanation. Sounds great!
 
I see, thanks for the explanation. Sounds great!
Did anyone actually read the articles? They make no sense.

The scientists put a normal wetsuit in a pressure chamber with heavy gas. That should accomplish zero. Neoprene wetsuits are closed cell. The gas current trapped in the inner bubbles is going nowhere. Nothing in, nothing out. Unless you break the bubble. And then the wetsuit is useless as it is now a sponge.

What am I missing?
 
What am I missing?

Gas slowly passes through and equalizes in the closed cells of the foam Neoprene. This was discovered in the early
experimental saturation dives. Wetsuits, hot-water heated and conventional, would compress with the divers in the chamber HeO2 environment. They would get thinner just like in the water. The suit thickness would slowly recover after a few days in the chamber. The big surprise came when they sent the suits out after the dive to make decompression more comfortable. They enlarged to about twice the size and basically exploded all the closed cells in the suit.

Hot water suits today are permanently compressed to collapse the cells to eliminate this problem and make the suits more flexible. That is how Dick Long discovered the process used on DUI's crushed Neoprene suits.
 
I just did the math to figure out how much positive buoyancy could potentially be shed from a 7mm wetsuit if the pores were replaced with a heavy gas like xenon instead of air. Looks like it's about 0.1 lbs best case...so not enough to make a difference.
 
Gas slowly passes through and equalizes in the closed cells of the foam Neoprene. This was discovered in the early
experimental saturation dives. Wetsuits, hot-water heated and conventional, would compress with the divers in the chamber HeO2 environment. They would get thinner just like in the water. The suit thickness would slowly recover after a few days in the chamber. The big surprise came when they sent the suits out after the dive to make decompression more comfortable. They enlarged to about twice the size and basically exploded all the closed cells in the suit.

Hot water suits today are permanently compressed to collapse the cells to eliminate this problem and make the suits more flexible. That is how Dick Long discovered the process used on DUI's crushed Neoprene suits.
So closed cell neoprene is not really "closed cell"?

I want to believe that for most practical purposes that neoprene is truly closed cell for most of its useful life - or else it would not work. Neoprene makes a crap sponge - which it would be if the cells exploded. Or degraded with age.

So what was their experiment? (@Akimbo explanation above slightly confuses me...) How much gas actually diffused into the closed cells? How fast? And for how long?
 
So closed cell neoprene is not really "closed cell"?

For reference, even a Rolex Sea Dweller is not really a "closed cell". All know known transparent materials act more like filters than barriers to Helium. That is why the Helium relief valve was invented.

During some early saturation experiments at the old Navy Experimental Diving Unit in Washington a couple of guys were decompressing. The chamber was small so they were sitting on a bench with their hands folded between their knees. All of a sudden the face of a Rolex watch blew out and hit a guy's inside thigh hard enough to make a serious edema, besides hurting like hell.

They did some research and found that Helium molecules will leak through all known transparent materials. The gas slowly leaked into the watch, which could easily take the external pressure but was never designed for internal pressure. They called Rolex, they put a tiny relief valve in a new watch with a deeper rating, named it the Sea Dweller, and called their Patent lawyers. The 17 year patent is long expired now.

The guy with a 1½" round scar on his leg was one of the Diving Officers when I was getting qualified, several years latter.

Closed cell foam Neoprene is pretty effective against large molecules like water, but not many glasses.
 
I just did the math to figure out how much positive buoyancy could potentially be shed from a 7mm wetsuit if the pores were replaced with a heavy gas like xenon instead of air. Looks like it's about 0.1 lbs best case...so not enough to make a difference.

Yep. Even the heaviest gas is much, much less dense than water.
 
So what was their experiment? (@Akimbo explanation above slightly confuses me...) How much gas actually diffused into the closed cells? How fast? And for how long?

The experiments were to verify the safety of decompression tables for saturation diving in addition to developing all the required support systems. Typical dives would last between a week and a month. I can't say definitively how long it takes for complete equalization but 1/4" Rubatex G231n material would recover to what looked like full thickness in a couple of days.

The suits would also decompress at least as fast as the divers. They were fine as long as they were not locked-out and brought to the surface in a few minutes.

Think of closed cell foam Neoprene like lung tissue. Gas passes across the tissue quite rapidly while red blood cells don't.

The biggest problem I see with the concept described in the OP is the less thermally conductive gas will leak out of the Neoprene cells pretty quickly. This is the same problem with Argon filled multi-pane windows. The great majority of Argon leaks out with virtually zero differential pressure in less than five years through a process called diffusion. In this case, most of it leaks through the edge seals much more rapidly than the glass.

Look close enough and you will see why very few non-metallic materials have zero gas permeability. Bone is one of the slowest tissues in the body for decompression calculations. This is what healthy human bone looks like under a scanning electron microscope.

full.jpg
 
https://www.shearwater.com/products/perdix-ai/

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