What is nylon raw material





Epoxy resins
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Rayon
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 Polyamides
Aramids
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polyester
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Plastics to get to know:

Polyamide - nylon


Polyamides are macromolecules in which the monomers are linked to one another by amide bonds or peptide bonds.

Natural polyamides are peptides and proteins, e.g. hair, wool, silk and egg white. Synthetically produced, long-chain aliphatic polyamides are also called nylon after the first pure synthetic fiber that Du Pont brought onto the market in 1939. Polyamides that contain only aromatic residues and therefore have special properties are called aramids.

Synthetic polyamides, which are abbreviated as PA (for P.olyA.mid), are the oldest really usable synthetic fibers and are still among the most important synthetic fibers in terms of quantity. Important representatives of the polyamides are nylon 6,6 and Perlon®.

A distinction is made between two types of polyamides, based on their monomers: On the one hand, there is the AS type, in which the monomers are amino acids (abbreviated AS), i.e. substances that have both an amino and a carboxyl group as functional groups, on the other hand there is the AA-SS type, which is formed from two different monomers, namely a diamine (AA) and a dicarboxylic acid (SS).
The two groups can be distinguished using the nomenclature, and it also indicates the chain length of the monomers used:
Perlon is called polyamide 6, PA 6 for short. Since only one number is given, it is made from a single monomer (with 6 carbon atoms), so the monomer must be an amino acid, which is why Perlon belongs to the AS type of polyamides.
Nylon 6.6 (PA 6.6 for short), on the other hand, belongs to the AA-SS type: One monomer is a diamine with 6 carbon atoms, 1,6-hexanediamine (the first number indicates the number of carbon atoms in the diamine), the The second monomer is a dicarboxylic acid, also with 6 carbon atoms, namely hexanedioic acid.

But now to the chemical aspects:
Nylon 6,6 (and similar polyamides like nylon 6,10 etc.) is - as just mentioned - made from a diamine and a dicarboxylic acid by polycondensation:

Perlon can of course be produced from 6-aminohexanoic acid, but ε-caprolactam is normally used as the starting material, which is formed from 6-aminohexanoic acid by forming an intramolecular amide bond. The type of reaction is again a polycondensation, it only takes place in the presence of water, which is needed to open the rings (a reaction that is formed from cyclic monomers polymer chains is also called ring-opening polymerization).

A few more notes on the properties: The amide bonds in polyamides are very polar because they contain oxygen, and therefore there are strong intermolecular attractions. In addition, polyamides such as nylon and perlon have a very regular structure, which greatly facilitates the formation of crystalline areas and thus the formation of fibers.
Polyamides are well suited for use as synthetic fibers because they are thermoplastics and can therefore be easily processed from the melt. In addition, polyamide fibers have many properties that make them suitable for the manufacture of garments: They can be dyed, are lighter than silk, elastic, moth-proof, rot-proof and alkali-proof, and also wrinkle-free and tear-resistant. The prime example of the use of polyamides is nylon tights, which hit the US market around 1940.
Incidentally, Perlon hardly differs in its properties from nylon 6,6, it is the competing product that was patented by a group of German companies (including BASF, Bayer and Hoechst) after the Second World War, because Du Pont already had the patent for nylon 6.6 had.


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