I forget where (engineering toolbox??) was the only reference out of a bunch, incl. manufacturers stuff, that I found that listed isopropanol (other alchohols?) only as "moderately" reactive with polyester or nylon - but this was soaking in it for a long time (and it didn't say what grade they used - impurities can matter). And some used other "alcohols" like methanol in their tests. Don't soak the thing. For sap fests, I get 98% pharmaceutical grade isporopanol, by the case (1Liter bottles) and just dampen a spot on a cotton towel type rag and scrub the rope/ prussik, whatever till the goo is off. This doesn't saturate the rope fabric. Let it dry for short time (5 min) in the sun and the alcohol is gone. Really soiled stuff is washed in front load, cool water with Teufelberger scrubba, no spin. If it's just dirt, I wash the rope with cold tap water and a rope scrubber (we use these on climbing ropes dragged around in glacial till/ silt - little sharp rock bits) and dry outta the sun. On metal stuff (spurs, ascenders what have you) or on your vehicle, the isopropanol dampened rag thing works great too - you may want to put some car wax on the car paint after, if you're diligent. C3H8O works on sap from under elms infested with aphids too, really all sorts of stuff. And on pants, jackets too.
Oh and maybe I should say why by the case? We use it for sterilizing (note the specific term used - not disinfecting) pruning tools using alchohol (3 min) and then flaming and cool down. Esp with stuff with spores.
Goo removal using oils or other stuff seemed like more work and for rope, it left it slicked up a bit when I tried stuff like canola, but maybe I wasn't using it properly.
I do keep my sappy lanyards separate for those jobs, and try using camming devices some times rather than prussiks to save myself some dishes.
My 2 cents. Cheers.
