I have searched and searched for reasons why one would not substitute polycro for cuben in a sleeping quilt ( http://www.suluk46.com/RandD%20-%20RD4%20WLQ.html ), or clothing, or even a tent.

Wondering if someone might be able to point out why someone has not done this. I am thinking I am missing something about polycro.

Thanks in advance

Polycro is cool stuff but my understanding is that it's nowhere near as strong as cuben. The spectra strands inside cuben give it a huge amount of strength.

Also, polycro shrinks when it's exposed to heat. If you had a polycro tent and had it set up on a hot day it would shrink and warp...not ideal. This is from Gossamers Gear's page on their polycro groundsheets:

"WARNING: Since these sheets are made from shrink film they will shrink when exposed to extreme heat. We tested these sheets in heat this summer and found that the sheets shrink 1" to 2" (3 to 5 cm.) in width and up to 5" (13 cm.) in length. These sheets do not need to be in direct sunlight to shrink, just very hot temperatures."

Edited by dandydan on 10/28/2010 12:23:56 MDT.

I'm not sure if it comes in different strengths/thickness, but the polycro I have has nowhere near the strength of even the lightest cuben fiber. Head over to your local hardware store and pick some up. I'm willing to make a lot of weight sacrifices and even I wouldn't go with a polycro quilt....Of course, I wouldn't be against it, so if you think it is suitable for your style, give it a go.

Anything that can be easily ripped with the hand is unsuitable for backpacking IMO. HYOH though.