Which of the following are thermoplastic polymers?

Polythene, polystyrene, polyvinyls

The correct answer is 3. Polythene, polystyrene, polyvinyls.

Thermoplastic polymers are polymers that can be melted and reshaped repeatedly. They are typically made up of long, straight polymer chains that are held together by weak intermolecular forces. This allows the polymer chains to slide past each other easily when heated, which is why thermoplastic polymers can be melted and reshaped.

Polythene, polystyrene, and polyvinyls are all thermoplastic polymers. They are made up of long, straight polymer chains that are held together by weak intermolecular forces. This allows them to be melted and reshaped repeatedly, making them ideal for a variety of applications.

Urea-formaldehyde and bakelite are thermosetting polymers. They are made up of polymer chains that are cross-linked, which means that they are chemically bonded to each other. This makes them rigid and hard, but it also makes them less flexible than thermoplastic polymers. Thermosetting polymers cannot be melted and reshaped once they have been cured.

So, the answer to the question is 3. Polythene, polystyrene, polyvinyls. These are all thermoplastic polymers, while urea-formaldehyde and bakelite are thermosetting polymers.