Problem 5 - Entrance Test

Bakelite is a thermosetting polymer formed by the condensation polymerization of phenol and formaldehyde. It is highly cross-linked and rigid. Melamine-formaldehyde resin is also a thermosetting polymer formed by the condensation polymerization of melamine and formaldehyde. Both are indeed thermosets and form cross-linked structures, meaning they cannot be remelted once formed. Option A is incorrect as both are thermosetting polymers, not thermoplastics. Option C is incorrect as they are condensation polymers, not addition polymers. Option D is incorrect; while both are heat-resistant, Bakelite generally has very high heat and chemical resistance and is known for its electrical insulating properties. Melamine resins are particularly known for being scratch-resistant and used in dinnerware. There isn't a general rule that Melamine has a 'higher degree of cross-linking' or is 'more resistant' overall, as properties depend on processing. Option B accurately states their respective monomers, which is the fundamental difference.