Expanded polyethylene (ePE)
Expanded polyethylene (ePE) is a strong, yet lightweight material that helps make gear durably waterproof without using perfluorinated chemicals.
Why
Membranes are a sometimes overlooked but critical component of waterproof gear. Bonded to the inside of your gear’s exterior shell, this thin inner layer of material has holes that are small enough to keep water from seeping in, but not so small that sweat can't vaporize out. For years, membranes have been made from expanded polytetrafluoroethylene (ePTFE)—an extremely hydrophobic and durable material. They worked well, but there was a problem: ePTFE is made with perfluorinated chemicals (commonly known as PFCs and PFAS). Though safe in finished products, these synthetic compounds can end up in the air and water during manufacturing processes. They’ve also been linked to increased cancer risk. And the compounds don’t break down. Perfluorinated chemicals remain in the environment—and in our bodies—indefinitely. We needed to come up with an alternative.
Where We Are
Nearly 10 years ago, we partnered with GORE-TEX to start building waterproof gear without PFCs or PFAS for the most technical mountain sports. These non-fluorinated products would have to withstand the most extreme conditions of snow and backcountry terrain, while also keeping you dry, comfortable and protected. Achieving that level of uncompromising durability has been challenging, but thanks to GORE-TEX's research, development and testing—and our own rigorous tests in the lab and field—we’re finally there.
In Fall 2022, we launched the 2-layerStorm ShiftJacket and Pants built with GORE-TEX’s expanded polyethylene (ePE), eliminating the need for long-lasting perfluorinated chemicals while still meeting Patagonia and the GORE-TEX brand’s high standards* for waterproof and windproof protection, as well as breathability.
For Fall 2023, we’ve introduced a three-layer iteration of GORE-TEX ePE that withstands the most rugged and demanding mountain experiences for some of our pinnacle technical Alpine and Snow pieces: the Triolet Jacket and Pants, the Super Free Alpine Jacket, the Alpine Suit, the Untracked Jacket and Bibs, and the Storm Shift Jacket and Pants.
This fall, we’ve added the 2-layer Insulated Storm Shift Jacket and Pants plus the 3-layer Untracked Pants made with GORE-TEX's ePE fabrics.
What’s Next
ePE is part of Patagonia’s broader goal to shift toward making gear without perfluorinated chemicals across all of our products by 2025. As we find more responsible options, we hope to inspire others in the clothing industry to redefine what’s possible for waterproof gear.
*For more on GORE-TEX's sustainability goals, see https://gtx.is/pfcec.
