Good old Ben's, sold in an HDPE bottle (what does that tell you about DEET and Dyneema?).
Soaking.
Will DEET insect repellent ruin your nylon climbing rope?
This has been answered many times before, yet still the web
persists with seemingly authoritative sources claiming DEET is death for nylon.
Unfortunately some of the most informative tests – performed by Honeywell and reported by Sterling years back –
have been scrubbed from the Sterling website, now exist only as quotations.
From MountainProject:
"Many
climbers have in the past worried about the effects of accidentally spilling
bug repellent on their climbing ropes. The following is the result of
preliminary testing of deet and other bug repellent chemicals.
Samples of nylon, polyester, and spectra were submitted for chemical resistance
testing for DEET (N,dimethyl-m-toluamide). The three samples were immersed
separately in CUTTER and OFF brand insect repellent for a period of twenty-four
hours at room temperature. OFF? contains 95% Deet (N-dimethyl-m-toluamide)
while CUTTER contains only 7% Deet and probably some oil based solvents as
well. The results of the testing indicate no loss of strength as measured by
tensile strength retention in any of the three samples.
There was one interesting anomaly that occurred only in the case of Nylon and
the "CUTTER? brand insect repellent. As mentioned before there was no loss
of strength for any of the samples but here there was a 25% increase in the
elongation and a decrease in modulus. This basically means that a rope made
entirely or mostly out of Nylon may become “rubbery� with a significant
amount of exposure to CUTTE? or other insect repellents with large amounts of
oil based solvents.
However, with regard to the chemical in question, DEET, there appears to be no
effect on any of the physical properties of the three samples. Hence as CUTTER?
contains only 7% DEET the change in the Nylon elongation and modulus must come
from the other solvents in the product. It is suggested that if a rope has
significant amounts of Nylon to use insect repellents with 95-100% Deet instead
of ones with some Deet and large amounts of other oil based solvents."
My Tests
So many of you are still skeptical? I did my own tests, just
for familiarity. I used Sterling 5mm nylon kernmantle cord. Three samples were
soaked in DEET for 4 days, then pulled out and allowed to sit for 4 days
outdoors in Las Vegas, when the daytime high often exceeded 100F. Two untreated
samples were kept as controls. After 4 days, the soaked cords still smelled
strongly of DEET.
Good old Ben's, sold in an HDPE bottle (what does that tell you about DEET and Dyneema?).
|
Soaking. |
Next I used mini-capstan clamps – made from ¾” bow
shackles—to move the breaking strength to higher levels than would be obtained
with knots, and used my Jeep to supply force (which was measured by a linescale 3):
Results:
That’s good enough for what I do. Notice all broke higher than the Sterling quoted “strength” – I suspect Sterling really tests figure-eight-to-figure-eight, or just gives a large comfort margin.
DEET does dissolve acetates and acrylics-- as in most spray
paints, ABS plastics (used in some climbing helmets), eyeglass frames,
some contact lenses, and the resin in Sharpie marks. In the test above,
I had marked off the area where I intended to apply the DEET with
Sharpie marks 2" to each side. The DEET wicked up and blurred the
Sharpie marks. We are used to thinking of ABS plastic as very tough ...
and it is resistant to impacts, but may get sticky if you touch it with
fingers that have been used to apply DEET. But your nylon... while it may stink... is pretty safe.