cavepaw wrote:Hello everyone:
Does anyone know of any sources for data on thermal degradation of Nylon?
I know it melts at 374-663F,
but I'm curious if there has been a study on the weakening of rope before melting.
Whoa! Where'd you get those temperatures?
What I'm looking at now** says 258^C for Type 6.6 & 218^C for Type 6,
which is 496 & 424^F, resp., per some on-line converter.
[**
Handbook of Fibre Rope Technology ]
The book has some interestingly inconsistent assertions,
though : in one place (Table 12.3, p.253) is gives as the
Safe Working Temperatures (Long term : > 1 month)
60 - 50 - 60 (all ^C) for, resp., Nylon - Polyester - HMPE (!)
and short-term ("up to 10 minutes")
70 - 200 (!) - 80 .
(Quite surprised to see HMPE working safely at nearly
half-way to its melting point of 150^C !)
Elsewhere, there comes a general statement that
nylon & polyester should be limited to 90^C, and
HMPE 50^C. !?
Back to Table 12.3, it also gives ("Information from yarn
manufacturers and other sources") :
Approx. values (over 0 .. 50^C range)
drop in strength (modulus) per 10^C [rise, presumably]
for resp. as above ... 2.5% (3%) - 2.5% (3%) - 6% (4%).
*kN*