Give preparation and uses of Nylon 6, 6.

Hint: It is a condensation polymer of a diamino compound and a di-carboxylic acid compound. It is a fibre polymer thus possessing high tensile strength and high modulus. It is also of crystalline nature due to close packing of chains caused by hydrogen bonding.

Complete step by step answer:
-Nylon 6,6 is a type of nylon or polyamide.
-It is formed by the polycondensation of adipic acid and hexamethylenediamine under high pressure and high temperature conditions.
Adipic acid: Its molecular formula is $HOOC{(C{H_2})_4}COOH$ and its IUPAC name is 1,6-hexanedioic acid.
Hexamethylenediamine: Its molecular formula is ${H_2}N{(C{H_2})_6}N{H_2}$ .
Now let us see that reaction for the preparation of nylon 6, 6:

-Now let us talk about the uses of Nylon 6,6.
Due to its high mechanical strength, rigidity and high stability even under high heat and chemical resistance nylon 6,6 has a large number of applications in the textile industry.

Due to its high tensile strength it is used for:
    -high speed mill processing
    -tyre applications
    -tough fibres, etc.
It also has excellent resistance for abrasion which makes it useful for:
   -conveyor belts
   -carpets and
   -upholstery
Apart from all this it is also used in making suspension lines, harness straps, tents, sleeping bags, sales, ropes, bristles for brushes, etc.

Note: Don’t get confused between nylon 6 and nylon 6,6. Nylon 6 is formed due to heating of caprolactam with water at high temperature while nylon 6,6 is formed due to condensation of adipic acid with hexamethylenediamine.