Which common material is an example of a polyamide?

Nylon 6,6 is a common example of a polyamide.

Polyamides are polymers that contain repeating amide (-CO-NH-) linkages.

The structure of Nylon 6,6 is  

[-NH-(CH_2)_6-NH-CO-(CH_2)_4-CO-]_n

where n is a large number.

The numbers in the name showow that there are six carbon atoms on either side of an amide linkage.

the number of protons in the nucleus of a given element. has slight luster and conducts electricity at high temperatures like metal.but like a nonmetal,boron is brittle and does not conduct electricity well at low temperatures. in graphite, carbon is a soft,brittle solid.it is reflective,ductile,or malleable.