Question

Novolac is:
A. a linear condensation product of phenol and formaldehyde
B. a cross linked condensation product of urea and formaldehyde
C. a cross linked condensation product of phenol and formaldehyde
D. A linear condensation product of urea and formaldehyde.

Answer 1

Novolac is a type of linear condensation polymer. The generation of Novolac takes place in the presence of an acid catalyst and a base catalyst.

Complete step by step answer:
We know that Novolac is an example of linear condensation polymer. Novolac is prepared by the reaction of phenol and the formaldehyde. These two molecules react in the presence of either a base or an acid catalyst. We can write the reaction of this preparation as follows.

So from this, we can conclude that Novolac is a linear condensation product of phenol and formaldehyde.
Therefore, option A is the correct option.

Additional information:
A polymer consists of repeated monomer units. Condensation polymers are step growth polymers which are formed by a condensation reaction. In such polymers, the molecules join together and they lose small molecules in the form of by-products such as that of methanol or water. Some examples of condensation polymers that occur naturally are cellulose, poly (β-hydroxybutyric acid), the polypeptide chains of proteins etc.

Note:
Novolac and Bakelite are inter-related. Novolac is a linear structure which is formed as a product of the condensation reaction between formaldehyde and with the excess of phenol. On further heating Novolac with that of formaldehyde undergoes cross linking forming an infusible solid mass. This solid mass is the Bakelite.