Tag: polymer

Questions Related to polymer

In vulcanization of rubber :

  1. sulphur reacts to form a new compound

  2. sulphur cross-links are introduced

  3. sulphur forms a very thin protective layer over rubber

  4. all statements are correct


Correct Option: B
Explanation:

Vulcanisation of rubber-

To improve these physical properties,
  • Strength
  • Resistance for oxidation
  • Repulsion from water
 a process of vulcanisation is carried out. This process consists of heating a mixture of raw rubber with sulphur and an appropriate additive at a temperature range between $373 K to 415 K.$ On vulcanisation, sulphur forms cross links at the reactive sites of double bonds and thus the rubber gets stiffened.

The correct option is [B].

Sulphur is used in  the vulcanization of rubber.

  1. True

  2. False


Correct Option: A

Vulcanization of rubber helps to make rubber hard and resistant to hot and cold conditions.

  1. True

  2. False


Correct Option: A
Explanation:

Vulcanization is a process in which the strength, stability, and elasticity of rubber are increased by subjecting it to heat, in the presence of sulphur. As a result, cross-linking occurs between the chains of rubber molecules and sulphur atoms.

The process involving heating of rubber with sulphur is called ___

  1. Galvanisation

  2. Vulcanization

  3. Bessemerisation

  4. Sulphonation


Correct Option: B
Explanation:

Vulcanisation of Rubber - Natural rubber  becomes soft at high temperature (>$335$ K) and brittle at low temperature (<$283$ K) and shows high water absorption capacity.
The process of  vulcanisation includes heating of raw rubber with sulphur and an appropriate additive at temperature range between $373$ K  to $415$ K. Sulphur foms crosslinks at reactive sites of double bonds and thus, rubber gets stiffened.

The synthetic polymer which resembles natural rubber is:

  1. Neoprene

  2. Buna-S

  3. Nylon

  4. Rayon


Correct Option: A
Explanation:

Neoprene resembles natural rubber. 


Natural rubber is a linear polymer of $2$-methyl-$1,:3$-butadiene called as isoprene and Neoprene is a linear polymer of $2$-chloro-$1,:3$-butadiene called as chloroprene.

Option A is correct.

Chloroprene is used in making

  1. synthetic rubber

  2. plastic

  3. petrol

  4. All of the above


Correct Option: A
Explanation:

Chloroprene is the monomer of neoprene, a synthetic rubber formed by the free radical polymerisation of choloroprene.


$nCH _2-CCl-CH=CH _2 \xrightarrow {Polymerisation} -[CH _2-CCl=CH-CH _2]-$

The process of vulcanization was introduced by ____

  1. Charles Goodyear

  2. Kolbe

  3. Wohler

  4. Zeigher


Correct Option: A
Explanation:

Charles Goodyear invented vulcanization process in $1839$.
Vulcanisation is a process involving heating of rubber with sulphur is called vulcanisation.

The tensile strength, elasticity and resistance to abrasion can be increased by a process called ___

  1. Galvanisation

  2. Vulcanization

  3. Bessemerisation

  4. Sulphonation


Correct Option: B

Which of the following is used in making automobile tyres and foot wear?

  1. Vulcanised rubber

  2. Neoprene

  3. Plexi glass

  4. Glyptal


Correct Option: A
Explanation:

Vulcanised rubber is used in making automobile tyres and foot wear. Heating of rubber with sulphur is called as vulcanisation. It makes the rubber hard and more flexible.

Vulcanization of rubber helps to make rubber hard and resistant to hot and cold conditions.

  1. True

  2. False


Correct Option: A
Explanation:

Vulcanization of rubber is a chemical process used for converting natural rubber into more durable material by addition of sulphur.
Vulcanization of rubber helps to make rubber hard and resistant to hot and cold conditions.