Question

Terylene is the polyester of?
A) Hexamethylenediamine and adipic acid
B) Vinyl chloride and formaldehyde
C) Melamine and formaldehyde
D) Ethylene glycol and terephthalic acid

Answer 1

Hint: as we know that a polymer is a substance that contains very large molecules or macromolecules which are basically composed of repeating units called monomers. Terylene also known as Dacron which is a polyester having ester linkages which are resultant of condensation of carboxylic acid and hydroxyl group.

 Complete step by step answer:
As we know that condensation polymerisation involves a repetitive condensation reaction between two bi-functional monomers. One such product of condensation polymerisation is terylene.
Terylene is commonly called as Dacron which is formed from the condensation polymerisation of ethylene glycol and terephthalic acid at a temperature of about $420 - 460K$ and it is a type of polyester which is obtained by the condensation reaction between a carboxylic acid and a hydroxyl group.
We can show this overall reaction as:

Hexamethylenediamine and adipic acid react under high pressure and temperature to form $Nylon - 6,6$ which is used in making sheets, bristles and in the textile industry. Vinyl chloride is generally used to make poly vinyl chloride (PVC) which is used in manufacturing of rain coats, hand bags etc. Formaldehyde and phenol is used to form Bakelite which is used for making combs, electrical switches, utensil handles and computer discs etc. and melamine along with formaldehyde results in the formation of melamine resins which are durable thermosetting plastics and thus used in decorative lanterns etc.
Therefore, the correct answer is (D).

Note: Remember that terylene is used in making fashion garments fabric, for laundry usage as a vacuum packaging machine and it is also used to make non-woven needle punched carpet for exhibitions. It is highly resistant to degradation by chemical bleaches and to abrasion.