A synthetic linear polymer in which the linkage of the simple chemical compound or compounds used in its production takes place through the formation of amide groups, e.g.,
[- R – CO – NH – R – CO – NH -] n or
[-R1 -NH-CO-R2-CO-NH-] n,
where R, R1, and R2 are generally, but not necessarily, linear divalent hydrocarbon chains (- CH2-) m.
Polyamides are distinguished from one another by quoting the number of carbon atoms in the repeating unit, or units for polyamides made from two reactants. In the latter case, the number of carbon atoms in the diamine is given first, this being followed by the number in the dicarboxylic acid,
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