Tuesday, April 10, 2012

Potpurri

Some random musings:
  • Nylons were originally inspired by proteins - both have polyamide linkages along their backbones which are made during the polymerization steps either biologically or synthetically. Most nylons have straight hydrocarbons between these linkages while the proteins have 20 different side arms, one for each of the 20 essential amino acids. If you were to prepare a nylon using α-amino carboxylic acids, you would end up with a nylon-2, a very rare entity indeed. Here's the structure of protein and nylon-6 for comparison:
    The Rx are the various moieties in the amino acids that are tabulated elsewhere.
  • 50+% market share is pretty rare, but does occur if you have a really good product. Two examples that I ran across recently were toothbrushes and sunscreen. In both cases, the 50+% market share was actually that of suppliers to the end product, rather than the end products themselves. Specifically, half the tooth brushes are made on machines made by the Zahoransky Group in Germany and half the sunscreens sold have UV absorbers made by BASF.

2 comments:

Anonymous said...

I'm new to (synthetic) polymers, so I'll ask you in advance for your kindness if this comment is off-point. It seems that calling Nylon-2 "protein" really only holds for R=H, which gives polyglycine. The generic structure for Nylon-6 you've provided doesn't seem to allow for any branching off the main-chain, variable or otherwise. This variable side-chain feature of the protein as a polymermic structure can be aliphatic, aromatic, acidic, or basic, which leads to a large sequence-space, within which relatively small and sporadic pockets of functional proteins and protein complexes arise. Still, this is an interesting comparison for someone like me with a biomolecule background now less than a year into a job with a coatings company.

John said...

Anonymous,

You are correct about the lack of branching and functionalization in nylons. (Polyamides however, have no such restriction.) They are linear aliphatic polyamides so there is no branching and only -CH2- groups between the amide groups. That then means as you stated that nylon-2 would be limited to polyglycine and that proteins would are functionalized nylon-2.

I was being sloppy and loose with the nomenclature.