Question

Amongst the following the total number of thermoplastics is: Polyethene, PVC, Teflon, PAN, PMMA, polyester, Bakelite, nylon 6, melamine formaldehyde.

Answer 1

Hint: A polymer defines a very large molecule consisting of a large number of monomers. Plastic is also a polymer made of many molecules of polymer. There are two classifications of plastics, such as thermoplastic and thermosetting plastics.

Complete Step by Step Solution:
Let's first understand the difference between the two types of plastics in detail.

Thermosetting Plastic	Thermoplastic
The nature of this plastic is brittle, that is, it breaks if we try to bend it.	The nature of this plastic is flexible, that is, it can be bent easily.
They are synthesised by the process of condensation polymerization.	They are synthesised by the process of addition polymerization.
In this plastic, the bond between the intermolecular chains is strong.	In this plastic, the bond between the intermolecular chains is weak.
Their durability is high.	Their durability is less.
When heated, they do not undergo deformation.	When heated, they undergo deformation.

Thermoplastic: Polyethene, Teflon, PVC, PAN, Polyester, PMMA, Nylon-6.
Thermosetting plastic: Melamine formaldehyde, Bakelite
Therefore, there are seven numbers of thermoplastics among the given polymers.

Note: It is to be noted that thermosetting plastics are useful in making electrical switches, handles of utensils, etc. The vulcanised rubber is also a thermosetting plastic. Also, we should be careful while working with thermoplastics because of the release of toxic fumes during the process of moulding.