I'm going to need to retire the dyneema dogbones on my quick draws in about another year. As I'm researching new ones I notice that a lot of people like the Petzl Express dogbones. And that the Black Diamond Vari-width and Standard Dogbones are inexpensive and easy to find. All of these are made of polyester.
What do we know about the lifespan and wear characteristics of polyester in climbing gear? I couldn't find anything about it. Where as there seems to be a lot information out there about nylon and dyneema.
Black Diamond says in the user manual for those two dogbones:
The maximum lifespan of Black Diamond sewn slings is up to 10 years from the date of manufacture (even if unused and properly stored). With normal use and proper care the typical lifespan of a sewn sling is two to five years. The actual lifespan can be longer or shorter depending on how frequently you use it and on the conditions of its use.
The only information I could find with Petzl is ten years is the maximum life span and inspect your gear regularly.
Anyone have any information about how long polyester should be used in this application?
While I can't answer your question, I know that polyester is used in some static ropes e.g. Sterling's HTP series, as well in some tents designed for long life at high elevation (where sunlight can destroy a nylon tent in a couple months).