Question:
The polymer formed on heating Novolac with formaldehyde is :
The polymer formed on heating Novolac with formaldehyde is :
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Novolac = Linear polymer; Bakelite = Cross-linked (3D network) polymer derived from Novolac.
Updated On: Dec 31, 2025
- Melamine
- Bakelite
- Polyester
- Nylon 6,6
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The Correct Option is B
Solution and Explanation
Step 1: Understanding the Concept:
Bakelite is a thermosetting phenol-formaldehyde resin. Its synthesis occurs in two main stages depending on the phenol-to-formaldehyde ratio and the catalyst.
Step 2: Detailed Explanation:
1. Phenol reacts with formaldehyde in the presence of an acid or base catalyst to form hydroxy-methylphenols.
2. Condensation of these monomers leads to a linear polymer called **Novolac**. Novolac is often used in paints and coatings.
3. When Novolac is further heated with additional formaldehyde (or hexamethylenetetramine), cross-linking occurs between the linear chains.
4. This cross-linked, infusible solid mass is called **Bakelite**.
Step 3: Final Answer: The polymer is Bakelite.
Bakelite is a thermosetting phenol-formaldehyde resin. Its synthesis occurs in two main stages depending on the phenol-to-formaldehyde ratio and the catalyst.
Step 2: Detailed Explanation:
1. Phenol reacts with formaldehyde in the presence of an acid or base catalyst to form hydroxy-methylphenols.
2. Condensation of these monomers leads to a linear polymer called **Novolac**. Novolac is often used in paints and coatings.
3. When Novolac is further heated with additional formaldehyde (or hexamethylenetetramine), cross-linking occurs between the linear chains.
4. This cross-linked, infusible solid mass is called **Bakelite**.
Step 3: Final Answer: The polymer is Bakelite.
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