Coupon Accepted Successfully!



Which of the following is a syndiotactic polymer in Description: 49512.png?
  1. All Y groups lie on one side of the chain and all Z groups on the other side
  2. The Y and Z groups lie alternately on each side of the chain
  3. The Y and Z groups are arranged in a random fashion
  4. Y and Z groups are same
Solution (B)
Three stereochemical arrangements are possible:
  1. Isotactic (same order): Here groups are arranged on one side of the chain. All Y groups lie on one side and all Z groups on the opposite side of the chain.
  2. Syndiotactic (alternating order): The Y and Z groups lie alternately on each side of the chain.
  3. Atactic (random order): The Y and Z groups are arranged in a random fashion.


The degree of crystallinity of which of the following is highest?
  1. Atactic polyvinylchloride
  2. Isotactic polyvinylchloride
  3. Syndiotactic polyvinylchloride
  4. All of these
Solution (C)
Syndiotactic polyvinylchloride
Description: 49519.png
In this arrangement, the chlorine atoms are alternately arranged. The polymer is stereoregular and has high crystallinity.


The synthetic polymer which resembles natural rubber is:
  1. neoprene
  2. chloroprene
  3. glyptal
  4. nylon
Solution (A)
In neoprene, monomer unit is
Description: 49528.png (chloroprene)
while isoprene Description: 49535.png is the monomer of natural rubber.


Three-dimensional molecules with cross links are formed in the case of a:
  1. thermoplastic
  2. thermosetting plastic
  3. both
  4. none
Solution (B)
Thermosetting plastics have a three-dimensional cross-linked structure. Such polymers are prepared in two steps. The first step is the formation of long-chain molecules, which are capable of further reaction with each other. The second step is the application of heat, which causes a reaction to occur between the chains, thus producing a complex cross-linked polymer.


Example of condensation polymer is:
  1. Formaldehyde → meta-formaldehyde
  2. Acetaldehyde → para-aldehyde
  3. Acetone → mesityl oxide
  4. Ethene →polyethene
Solution (C)
Polymers formed by condensation process with the elimination of small molecules such as Description: 49544.png, etc., are known as condensation polymers.
For example,
Description: 49552.pngDescription: 49561.png

Test Your Skills Now!
Take a Quiz now
Reviewer Name