Organic chemistry
Since the invention of the first synthetic polymer product, bakelite, synthetic polymer products have frequently been invented.
Nylon
The nomenclature used for nylon polymers was devised during the synthesis of the first simple aliphatic nylons and uses numbers to describe the number of carbons in each monomer unit, including the carbon(s) of the carboxylic acid(s). Subsequent use of cyclic and aromatic monomers required the use of letters or sets of letters. One number after 'PA' or 'Nylon' indicates a homopolymer which is "monadic" or based on one amino acid (minus HO) as monomer: