Phenolic vs other thermosets: formaldehyde condenses with which substrate to produce a non-phenolic resin?

Introduction / Context:Condensation of formaldehyde with various nucleophilic substrates yields different thermoset families. Phenolic resins result from phenol-formaldehyde reactions, while melamine-formaldehyde resins constitute a separate class with distinct performance.

Given Data / Assumptions:

• Phenolic substrates include phenol, resorcinol, and p-substituted phenols like p-cresol.
• Melamine is a triazine amine, not a phenolic compound.
• Formaldehyde acts as a crosslinker via methylol formation.

Concept / Approach:Phenolic resins require phenolic hydroxyl groups. Amino resins (e.g., melamine–formaldehyde) form by condensation at amino groups, producing methylene and methylene-ether linkages typical of MF resins, known for hardness and heat resistance.

Step-by-Step Solution:List phenolic candidates: phenol, resorcinol, para-cresol.Identify melamine as non-phenolic (amino) substrate.Therefore, melamine with formaldehyde does not produce a phenolic resin.

Verification / Alternative check:Commercial tabletop laminates and dinnerware often use melamine–formaldehyde, not phenolics, highlighting the different resin family.

Why Other Options Are Wrong:Phenol/resorcinol/p-cresol all yield phenolic-type networks with formaldehyde.

Common Pitfalls:Assuming all formaldehyde condensations are “phenolic”; overlooking amino resins as a major thermoset class.

Final Answer:Melamine