Which of the following polymers are condensation polymers? (i) Bakelite (ii) Teflon (iii) Butyl rubber (iv) Melamine formaldehyde resin

Option (i) and (iv) are the answers.

Bakelite is a phenol and formaldehyde condensation polymer. Melamine formaldehyde resin is a melamine (2, 4, 6-triamino-1, 3, 5-triazine) and formaldehyde condensation polymer.