Problem 99 - Advanced Problems in Organic Chemistry for Competitive Examinations

Question

A polyamide synthetic polymer prepared by prolonged heating of caprolactum is (a) glyptal (b) nylon-6 (c) nylon-6, 10 (d) nylon-6, 6

Step-by-Step Solution

Answer

The answer is (b) nylon-6.

Step 1: Understanding the Exercise

We need to identify which polyamide synthetic polymer is formed by the prolonged heating of caprolactum. The options provided are different types of polymers commonly used for various applications.

Step 2: Identifying Caprolactam

Caprolactam is a monomer used in the production of a polymer. Caprolactam is specifically known for being involved in the production of a type of nylon.

Step 3: Linking Caprolactam to Nylon-6

Caprolactam, through a polymerization process, specifically forms a single type of polymer, which is nylon-6. Unlike other nylons, such as nylon-6, 6, nylon-6, 10, or glyptal, it directly associates with polyamide nylon 6.

Step 4: Conclusion

Based on the polymerization of caprolactam, the polyamide synthetic polymer produced by its prolonged heating is nylon-6, which is option (b).

Key Concepts

Caprolactam

Caprolactam is an integral player in the world of synthetic polymers. It acts as the monomer building block primarily for producing nylon-6. Caprolactam itself is a cyclic amide that can be opened up during the polymerization process to form long polymer chains. This enables it to be used on a large scale for industrial polymer synthesis.

Key characteristics of caprolactam include:

• It is a white, crystalline solid.
• It has a slight ammoniacal smell.
• Solubility in water which aids in its utility in polymerization.

Through these properties, caprolactam becomes the starting point for a range of applications making it indispensable in producing valuable polymers such as nylon-6.

Nylon-6

Nylon-6 is a well-known polymer related closely to caprolactam. It is renowned for its widespread use, particularly in textiles and plastics, where strength and durability are required. Nylon-6 is categorized under polyamides, a family of polymers characterized by amide linkages in their backbone which are significant in contributing to their resilient properties.

The features that make nylon-6 appealing include:

• High tensile strength suitable for various industrial applications.
• Excellent resistance to abrasion and chemicals.
• Effective under a wide range of temperatures.

Due to these properties, nylon-6 is used in products such as carpets, non-woven fabrics, and molded parts for the automotive and electronics industries.

Polymerization Process

The polymerization process is crucial in transforming small monomers into larger polymers. In the case of caprolactam turning into nylon-6, this involves a specific type called "ring-opening polymerization." This process involves opening the ring structure of caprolactam under heat, allowing it to form long chains, ultimately resulting in polyamide nylon-6.

Steps in the polymerization process of forming nylon-6 include:

• Heating caprolactam to unlock its structure.
• Initiation step where the molecule starts forming the chain.
• Propagation step where the chain grows longer by continuous addition of caprolactam units.
• Termination, concluding the process once the chains have reached the desired length.

This polymerization process not only elucidates the unique capabilities of caprolactam in forming nylon-6 but also highlights the intricate chemistry underlying the development of synthetic polymers.