Recently a new kind of polymer has hit the outdoor fabric market: UHMWPE or ultra high molecular weight polyethylene. This material has a strength-to-weight ratio 15 times greater than steel and is being used to make modern bulletproof vests, commercial fishing nets, artificial hips and knees for joint replacements, and it's even replacing large steel chains in heavy industries all over the world.
In addition to its strength to weight ratio this modern superplastic has a handful of interesting properties that make it advantageous for use in outdoor fabrics: it has a low specific gravity so it floats on water, it's incredibly resistant to damaging environmental factors such as chemicals and UV light, it doesn't absorb water and it's almost completely static.
UHMPWE does however have a few properties that pose significant challenges when developing outdoor fabrics: it has a low friction coefficient so it's almost as slippery as Teflon, and it's extremely expensive.
There are many different ways to incorporate these fibers into outdoor fabrics and one of the most effective is to take a traditional nylon or polyester woven fabric and intersperse UHMWPE yarns into the weave, typically forming a ripstop grid. This allows for a construction that capitalizes on the high strength-to-weight of UHMWPE and imparts phenomenal tear strength to your fabric, but avoids the downside of slippery fibers; since the majority of your fabric is constructed with traditional nylon yarns seam integrity isn't an issue here.
We've chosen this type of fabric for the 70D reinforcement panels on the new Advanced Series bags so that our customers no longer have to choose between ultralight and robust.