Item	Unit	PA6	PA66
density	g / cm 3	1.10	1.15
melting point	℃	215~225	255~265
balanced water content	23℃, R.H.65%	3.5	2.5
strength	MPa	74	76
elongation rate	%	170	70
elongation modulus	GPa	2.6	2.9
Izodimpact strength	J/m	59	39
bending strength	MPa	108	108
bending elastic modulus	GPa	2.5	2.8
antigrease		even	even
chemicals		even	even
electrical insulation		even	even
rigidity			win
toughness			win
wear resistant			win
thermal resistant			win
fatigue resistant			win
mechanical strength			win
softness		win
impact resistant		win
process		win
Dye		win
finished surface		win
Price		win
Item	unit	PA6	PA66

Nylon is polyamide (abbrivated as PA), a condensation type of polymer coming with (-CONH-), that is mostly available in PA6 and PA66., in addutio to PA12, PA11, PA46, PA610, PA 612 demanded fewer in the market, number of which indicates number of carbon atoms in material monomer. The above-mentioned polymer materials are collectively called as nylon engineering plastics.

The unique property of PA is in its advantageous properties of mechanical strength, including toughness, antigrease, self-lubricating, and small coefficient of friction, while having disadvanteges of large humidity absorption that affects size stability. Though PA6 and PA66 are similar in structure, physical property differs significantly, as thermal resistance of PA66 is 50 degrees higher higher than that of PA6.

The advantageous properties of thermal resistance, grease resistance, mechanical strength of PA6 and of PA66 are the main reasons for their being applied to auto parts. In addition, through procedure of added with modifiers of inorganic matter, and glass fiber, they may be endowed with high folding property or suitable for treatments after plating or painting.