Question

Dacron is an example of:
(a) Polyamides
(b) Polypropenes
(c) Polyacrylonitrile
(d) Polyesters

Answer 1

Dacron is an example of the family of polymers which is a petroleum-based synthetic fibre. These contain ester groups.

Complete step by step solution:
-Polyester is a category of polymers which contain ester functional groups. Dacron contains an ester functional group.
-Polyethylene terephthalate also known as Dacron is a most common thermoplastic polymer resin of polyester family of polymers. It’s commonly abbreviated as PET or PETE etc.
-IT is used in fibres for clothing, containers for liquids and foods. It is also used in combination with glass fibre for engineering resins.
-Its chemical representation is

-Its monomer units are ethylene terephthalate. The monomer bis(2-hydroxyethyl) terephthalate is synthesized by the esterification reaction between terephthalic acid and ethylene glycol. It can also be synthesized by transesterification between ethylene glycol and dimethyl terephthalate(DMT) with methanol as a by-product.
-Dacron or PET in its natural state is colourless, semi-crystalline resin. When processed, it becomes semi-rigid and lightweight. It is very strong and is impact-resistant. When exposed to chloroform or other certain chemicals, PET turns white.
-Plastic bottles are made from PET which is used for soft drinks. When modified can be used for flexible food packaging and thermal insulation (such as space blankets). IT has a high mechanical strength and due to this it is also used in tape applications, such as magnetic tape or backing for pressure-sensitive adhesive tapes.

Thus, as Dacron consists of ester groups, it is a polyester and the option (d) is the correct answer to the question.

Note: There are many other names by which Darcon is known. It is known as Terylene in the United Kingdom and it is known as Lavsan in Russia. The name “Dacron” is mainly used in the United States.