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Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

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Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#161

Post by mint2 »

nwiswell wrote: post #75
xyst wrote: post #72

isn't this stuff in the same family as the "forever chemicals"?

Yep these are fluoropolymers. But I'm not sure how much that really matters... a regular un-fluoridated polymer like polyethylene that sticks around for a thousand years is not all that different in practice from a fluoropolymer that will stick around for a million years. If they're not recycled they go to landfill. Maybe more to the point, I'd much prefer to contaminate the environment with inert chemicals with a mi…

Except there’s many routes ptfe can turn harmful. If it burns it turns into horrible stuff. Guess it shouldn’t be used in California.

And just as with polyethylene, additives like plasticizers and various other components added for processing can be a big issue. They used to use pfoa for helping process Teflon. Who knows what they use now.

It’s probably unwise to be overly trusting.

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#162

Post by snowwrestler »

I find that most writing about Gore-Tex gets the mechanism of breathability wrong. Often I’ll see references to humidity or air pressure. I also see tons of statements that Gore-Tex can’t breathe if the DWR fails.

None of that is correct. Water moves through Gore-Tex via evaporation, and the driver is heat. As long as it is warmer on one side of the membrane than the other, moisture will move toward the colder side. This works even if both sides of the membrane are in direct contact with liquid water.

The ePTFE of Gore-Tex is like an open-cell foam, or an extremely dense net, whose holes are small enough to exclude liquid water drops, but huge compared to water molecules. It is not one-dimensional; it has thickness. It creates essentially a thin captive atmosphere within the membrane, through which water vapor can move.

If the membrane is immersed on both sides, water will be evaporating into the captive atmosphere within the membrane from both directions. Water vapor will also be condensing out of that atmosphere in both directions. So if one side is warmer than the other, there will be a net transfer of water from the warm to the cold side. On the warmer side it will be a bit easier for water to evaporate; on the cold side, a bit easier for it to condense.

In Gore-Tex the inner side of the ePTFE is mated to hydrophilic polyurethane (PU). This is to protect the ePTFE from oils and grease from our disgusting skin. So water vapor is soaked up by the PU, and once the PU is saturated, the water starts evaporating from the PU in both directions. But again, as long as there is a heat gradient, it will result in net moisture movement from warm to cold.

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#163

Post by account-5 »

I've had and goretex gear in the military and for hillwalking. I've always found the footwear to be too hot and causes my feet to sweat so much I get borderline trench foot. Waterproof wise it's only slightly better than non-goretex.

My personal opinion is the price isn't worth it. For wet weather I'll stick with wellies, good socks and a poncho.

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#164

Post by starefossen »

exabrial wrote: post #18

I recently learned in order for a product to have the Gore-Tex label, not only do you have to license the process/formula from them, but you have to send engineering samples to them and they perform their own independent testing before allowing you to actually sell the product. There’s no doubt part of the success is the chemistry of the product, but the required independent testing to very high standards also likely…

From what I have herd (but I was unable to find any written source at this point) the sampling only applies to the Gore-Tex Pro Shell brand. Meaning that products needs to be sent in and certified by Gore before they can be sold under that name.

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#165

Post by antman »

exabrial wrote: post #18

I recently learned in order for a product to have the Gore-Tex label, not only do you have to license the process/formula from them, but you have to send engineering samples to them and they perform their own independent testing before allowing you to actually sell the product. There’s no doubt part of the success is the chemistry of the product, but the required independent testing to very high standards also likely…

Gore tex has been many many years around, hasnt its patent expired?

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#166

Post by starefossen »

gorbypark wrote: post #50
exabrial wrote: post #18

I recently learned in order for a product to have the Gore-Tex label, not only do you have to license the process/formula from them, but you have to send engineering samples to them and they perform their own independent testing before allowing you to actually sell the product. There’s no doubt part of the success is the chemistry of the product, but the required independent testing to very high standards also likely…

Not only that, but Gore will honour their “guaranteed to keep you dry” warranty. I had a Gore-Tex jacket that the manufacturer refused to replace after it delaminated about 3 years after I bought it. One call to Gore and I got the purchase price of the jacket in a prepaid credit card sent to me after sending them the jacket.

According to their FAQ page this only applies to products with a “guarantee to keep you dry” label inside.

https://www.gore-tex.com/support/frequently-asked-questions

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#167

Post by ls15 »

samwillis wrote: post #17

The article doesn't mention (other than a brief nod to the brand) the other massive use of PTFE, none sticks surfaces originally under the Teflon brand, most commonly found on cookware. It truly is a "magic" material. Teflon and other PTFE based none stick surfaces are now really quite controversial due to the toxic gasses they can give off of you heat them too high. And the manufacturing processes is potentially lin…

> The industry is now moving away from PTFE to other materials for none stick surfaces, however although they proclaim these are "safe", they have been studied far less. I believe some evidence is indicative of them also having serious issues.

I've been moving away from PTFE in favour of cast iron cookware. Besides many other great properties, it is non-stick if used correctly.

https://old.reddit.com/r/castiron/comments/z4vdyd/some_slide...

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#168

Post by Maxion »

qbasic_forever wrote: post #108
alfor wrote: post #105

I didn’t know Gore-TEX was ptfe. Damn, those things last forever (like BPC). Think plastic is a problem? PTFE is way worse. Those are the microplastic we are going to find in breastmilk forever.

Yeah a lot of outdoor manufacturers have been trying to make more eco friendly waterproof gear that doesnt use PTFE. Patagonia in particular has been really trying hard to get rid of their use of them: https://www.patagonia.com/our-footprint/ptfe-polytetrafluoro... From what I understand the gear that doesn't use PTFE is unfortunately still not great or have the long term durability as goretex. Hopefully soon they'll…

Klättermusens Cutan fabric performs quite well. Especially compared with Gore.

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#169

Post by adnanc »

Having used a number of Gore-Tex products over the last 20 years, the breathability does suffer after some time.

For cycling, I’ve been using the Rapha Shadow range [0] which has been brilliant. It is on the expensive side but definitely worth it.

[0] https://www.rapha.cc/gb/en/stories/shadow-revolution

Re: Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE

#170

Post by morsch »

dleslie wrote: post #88
jerlam wrote: post #82

Gore-TEX and other waterproof breathable (WPB) membrane fabrics are ridiculously oversold to people who don't spend much time outside. The amount of breathability they offer is ludicrously low compared to something like unzipping a jacket zipper or pit vent. If you're moving at all, a WPB jacket means that you'll be drenched from the inside due to sweat, and all that water repelled by your jacket ends up on your pant…

In the PNW, particularly here in BC, Gore-TEX was an absolute game-changer for hikers. Throw on a tank top or tee-shirt, then your Gore-TEX jacket, and you could climb basically any local mountain between March and October, rain or shine. Every local hike went from being a moist, uncomfortable affair to being a joy regardless of the weather.

What about rain shedding off your jacket onto your pants? This has totally been an issue for me and in inclement weather I wear (non breathable) rain pants (apparently the right word is bibs).

Then again you only say to put on a t-shirt and a jacket, no mention of pants -- I guess that's one way to solve the problem.

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