Phenol and fomaldehyde undergo condensation to give a polymar (A) which on heating with formaldehyde gives a thermosetting polymer (B) Name the polymers. Write the reaction involved in the formation of (A) what is the structural difference between two polymers?

Explanation

The polymer (A) is a linear chain polymers known as Novolac white the polymer (B) is a cross linked polymer called Bakelite. For their structures, consult section 6