Problem 66 - A Complete Resource Book in Chemistry for JEE Main

Question

Which of the following statement is incorrect? (1) Vinyon is a copolymer of vinyl chloride and vinyl acetate (2) Saran is a copolymer of vinyl chloride and vinylidene chloride (3) Butyl rubber in a copolymer of isobutylene and isoprene (a) 1 and 2 (b) 2 only (c) 1 only (d) none is incorrect

Step-by-Step Solution

Answer

(d) none is incorrect

Step 1: Understanding the Question

The question asks for the identification of incorrect statements about specific copolymers. We have four statements, and we need to determine which one or ones are factually incorrect.

Step 2: Assessing Statement 1

Statement 1 claims Vinyon is a copolymer of vinyl chloride and vinyl acetate. Knowing that Vinyon is indeed made by copolymerization of these two compounds, this statement is correct.

Step 3: Assessing Statement 2

Statement 2 claims Saran is a copolymer of vinyl chloride and vinylidene chloride. Saran is known to be made from this combination, making this statement correct as well.

Step 4: Assessing Statement 3

Statement 3 claims Butyl rubber is a copolymer of isobutylene and isoprene. This is also correct because Butyl rubber is produced by polymerizing isobutylene with a small amount of isoprene.

Step 5: Analyzing Options for Incorrect Statement

Analyzing the truth of each of these statements shows that none of the given statements are incorrect. Therefore, 'none is incorrect' should be chosen.

Key Concepts

Vinyon

Vinyon is a unique synthetic fiber created from the copolymerization of vinyl chloride and vinyl acetate. This fiber is known for its distinctive properties which include high strength and resistance to moisture. These qualities make Vinyon particularly suitable for use in garments and industrial applications where durability is a priority.

• Vinyl chloride contributes to the fiber's toughness and chemical resistance.
• Vinyl acetate provides flexibility and enhances the fiber's handling ability.

Due to its low melting point, Vinyon is often used in applications that do not require exposure to high temperatures. Despite this limitation, its hydrophobic nature makes it useful in waterproof clothing and other moisture-resistant textiles.

Saran

Saran is best known as a copolymer comprised mainly of vinyl chloride and vinylidene chloride. This composition gives Saran its superior barrier properties, making it an excellent choice for packaging materials. Saran forms a clear, transparent, and flexible film that helps protect contents from air and moisture, significantly extending shelf life.

• Vinyl chloride plays a role in enhancing the clarity and processing ease of the film.
• Vinylidene chloride provides the impermeability crucial for preventing the passage of gases and moisture.

Not confined to packaging alone, Saran is also utilized in other areas such as plastic wraps and protective coatings, owing to its strength and environmental resilience.

Butyl Rubber

Butyl rubber is a remarkable material that results from the copolymerization of isobutylene with a small fraction of isoprene. This type of rubber is noted for its exceptionally low permeability to gases and its strong resistance to aging, ozone, and weathering. These properties make Butyl rubber ideal for a variety of applications:

• Isobutylene provides exceptional airtight qualities, crucial for manufacturing items like inner tubes and seals.
• Isoprene introduces a small amount of unsaturation, allowing for vulcanization and improving elasticity.

Butyl rubber is often found in products exposed to environmental extremes, such as automotive components and protective clothing. It strikes a balance between flexibility and impermeability, making it invaluable in industries where airtight properties are a necessity.