Problem 57 - A Complete Resource Book in Chemistry for JEE Main

Question

Synthetic rubber (neoprene) is (a) polyamide (b) polyester (c) poly halodiene (d) polysaccharide

Step-by-Step Solution

Answer

Neoprene is a poly halodiene.

Step 1: Understand the Question

The question asks us to identify the category or type of polymer that synthetic rubber (neoprene) belongs to. It gives us four different options to choose from: polyamide, polyester, poly halodiene, and polysaccharide.

Step 2: Analyze Each Option

Let's examine each type of polymer: - **Polyamide:** These are polymers containing repeating units linked by amide bonds, commonly known as nylons. - **Polyester:** These are polymers formed by ester linkage between monomers, used in fabrics and textiles. - **Poly halodiene:** These are made from halogenated diene monomers. Neoprene, a type of synthetic rubber, falls into this category because it is made from chloroprene. - **Polysaccharide:** These are carbohydrates formed by long chains of monosaccharide units, such as starch and cellulose.

Step 3: Identify Neoprene

Neoprene is a type of synthetic rubber, specifically made by polymerizing chloroprene. Chloroprene is a 2-chloro-1,3-butadiene, which is a halogenated diene, placing neoprene in the category of poly halodiene.

Step 4: Choose the Correct Answer

Based on our analysis, the correct category for neoprene is **poly halodiene**. It matches the characteristics of neoprene being a synthetic rubber derived from halogenated dienes.

Key Concepts

Polymers

Polymers are long chains of repeating molecular units known as monomers. These structures play a crucial role in a range of materials and products used in daily life.

The versatility of polymers stems from the different types of monomers and the various ways they are bonded together. This gives rise to diverse materials with unique properties suitable for different applications.

There are several categories of polymers, classified based on the type of repeating units and chemical bonds:

• **Thermoplastics**: These can be melted and reshaped multiple times.
• **Thermosets**: These become permanently hard upon being cured and cannot be remolded.
• **Elastomers**: These are flexible and can return to their original shape after being stretched.

Understanding polymers and their classes allows us to create materials like synthetic rubber, which mimics the qualities of natural rubber.

Neoprene

Neoprene is a synthetic rubber that is renowned for its resilience and versatility. This type of polymer is created by polymerizing the monomer known as chloroprene.

Chloroprene is a chemical compound that contributes to neoprene's characteristic properties. Neoprene is known for its:

• **Resistance to oil, chemicals, and weathering**: Making it suitable for outdoor and industrial applications.
• **Flexibility**: Allows it to be used in a variety of forms like wetsuits, gaskets, and protective gear.
• **Thermal insulation**: Made ideal for products that need to maintain warmth

Neoprene's ability to maintain performance under varying environmental conditions makes it a popular choice in manufacturing industries. Whether it’s to withstand harsh weather or industrial chemicals, neoprene plays a significant role in multiple industries.

Poly Halodiene

Poly halodiene refers to a category of synthetic polymers created from halogenated diene monomers. The term "halodiene" indicates that a halogen atom is attached to the diene's carbon atoms.

Neoprene is a type of poly halodiene, specifically derived from the monomer chloroprene—which contains chlorine—a halogen. This bonding is critical because it grants poly halodienes, like neoprene, their distinct properties:

• **Enhanced durability and chemical resistance**
• **Good elasticity and flexibility**
• **Resistance to degradation by ozone and other aggressive chemicals**

These unique characteristics make poly halodiene polymers suitable for specialty applications where traditional rubber might fail. It’s important to note that while neoprene is the most recognized example, the poly halodiene family includes other polymers with similar properties tailored to specific needs.

Polymer Types

Polymer types are generally classified based on the structure of their monomers and the nature of their bonding. This classification allows chemists and engineers to design materials that fulfill specific functions and requirements. Here is a brief overview of different polymer types:

• **Polyamides**: Known for high strength and resistance to wear, such as nylons used in textiles and engineering plastics.
• **Polyesters**: Often used in fabrics and plastics, offer properties like toughness and chemical resistance.
• **Polysaccharides**: Found in nature, these include starches and celluloses used in food and packaging industries.
• **Poly Halodienes**: Like neoprene, these are resistant to various environmental stresses, making them ideal for industrial uses.

Each polymer type brings a unique set of properties, allowing for a broad application range from clothing and packaging to industrial materials. Understanding these categories aids in selecting the right polymer for the desired application based on their inherent benefits.