All Plastics are only "plastic" due to their elastomers. The names of these chemicals which are needed in all plastics to retain their elasticity over time are very long. Anyways, Over time these elastomers "leak" out of plastics and they then become brittle.
In more modern plastics, the folks making said elastomers have made it so they "leak" out slower and add in the fact that they are adding more "elastomers" into said plastics like Nylon, PVC, ABS, HDPE, etc equates to a longer shelf life of plastics. Thus, ropes today have a much longer "shelf life" than old nylon ropes. Eventually, they will become brittle and break.
For instance if you see nylon slings around rocks in the mountains you don't expect them to any good because slings are not UV stabilized and they don't have as many expensive "elastomers" imbedded in them. Thus, it is VERY IMPORTANT TO REPLACE YOUR CLIMBING SLINGS WAY BEFORE YOUR ROPE!
This is one of the main concerns about data storage and CD's/DVD's the "coating" covering the data pits will degrade over time and one will not be able to "bend" those CD's/DVD's when moving them around without destroying the data like today.
Brian
As the UIAA wrote. Old ropes are fine, just that they can't take the abuse of new ropes due to fewer elastomers present and the whole rope will be more "brittle" and cut more readily over an edge.
Alpinisto wrote:woodsxc wrote:Woo hoo! I might get to keep one of the unused ropes!! Hooray!
n00bz!! UR gonna die!