Vicky, I'm not sure if the monofiliament will melt or not, but I asked a question about FMQ thread within the last week as I was considering monofilament for FMQ. The responses were definetly against using it for my purposes. So if it's in the quilt already, you may want to google about it; if not, you may want to read the other posts and reconsider.
good luck,
V.

There are two types, Vicky. One is poly and the other is a nylon. The nylon melts at a lower temperature and shouldn't be ironed. But I think poly would melt, too, if hot enough.

They say both can be used in a dryer but never set it on it's hottest.

Vicky,
I used some kind way back and I was not happy with the results.

I watched a quilting show and (can't remember who lol) they said that it has gotten a bad rap and today's mono threads are much better.

Sulky advertises that it can be ironed on cotton setting.
Rosa

Here is a link that might be useful: SulkyMonoThread