Melting point
6.6 melts at 250°C and nylon 6 at 225°C.

On burning, nylons burn less readily than cotton and rayon and tend to melt away from the flame.
Nylon fibres have a tendency to be self­- extinguishing. However, in bulk, a molten mass will burn fairly readily. On burning, nylon has a characteristic celery-like odour.

Nylon has good general resistance to acids, but will disintegrate on heating with concentrated acids.
Nylon is soluble in boiling 80 % acetic acid and in formic acid at room temperature. Nylon is resistant to alkali.

Nylon is not affected by the standard hydrocarbon, aromatic or chlorinated solvents.
Nylon is soluble in phenols, especially in-cresol.