Animated Solution for Chemistry - Organic Chemistry: Which polymer is used in the manufacture of paints and lacquers?

The world of polymers is not just a collection of complex chemical structures; it is the very foundation of the modern materials we interact with every single day. From the non-stick coating on your frying pan to the sturdy pipes in your walls, polymers are everywhere.

In this classic JEE Main problem, we are asked to identify which polymer is the secret ingredient behind the vibrant paints and protective lacquers that coat our furniture and vehicles. Let's embark on a journey of elimination and discovery to find the right answer!

To solve this, we must look beyond the names and understand the physical properties of each option.

1. Bakelite: The Heat Resistor First up is Bakelite. Synthesized from the condensation of phenol and formaldehyde, Bakelite is a thermosetting polymer. During its formation, it undergoes extensive cross-linking, resulting in a rigid, infusible, and insoluble solid mass. Because it is an excellent insulator of heat and electricity, it is the go-to material for making electrical switches, plug points, and the handles of cooking utensils. However, its insoluble nature means it cannot be dissolved in a solvent to form a liquid paint. Thus, Bakelite is out of the race.

2. Polypropene: The Tough Flexible Next, we have Polypropene (PP), an addition polymer formed from propylene monomers. Polypropene is known for its toughness, flexibility, and resistance to chemical fatigue. You will commonly find it in the form of sturdy plastic chairs, strong packaging materials, and ropes. While it is incredibly useful, it lacks the specific film-forming properties required to create a smooth, adhering layer of paint.

3. Polyvinyl Chloride: The Water Repellent What about Polyvinyl Chloride (PVC)? The presence of chlorine atoms in its long hydrocarbon chain gives PVC excellent water-resistant properties. This makes it the undisputed king of plumbing pipes, raincoats, handbags, and vinyl flooring. But just like Polypropene, it is not designed to be dissolved and spread as a thin, glossy film. PVC is eliminated.

Glyptal

This brings us to our final and correct option: Glyptal.

Glyptal is a fascinating polyester. It is created through the copolymerization of two specific monomers: ethylene glycol (ethane-1,2-diol) and phthalic acid (benzene-1,2-dicarboxylic acid).

When these monomers react, they form a polymer chain that has a slight degree of cross-linking. The true magic of Glyptal lies in its behavior when mixed with suitable solvents. It dissolves to form a viscous liquid. When this liquid is applied to a surface—like a wooden table or a metal car body—the solvent begins to evaporate. As the solvent leaves, the Glyptal molecules undergo further cross-linking, curing into a tough, continuous, and highly glossy film.

This exceptional film-forming ability is exactly what is needed for a high-quality coating. Therefore, Glyptal is extensively used in the manufacture of paints, lacquers, and enamels.

By logically connecting the chemical structure and physical properties of each polymer to its real-world applications, the answer becomes crystal clear. The polymer used in the manufacture of paints and lacquers is indeed Glyptal.

Whenever you study polymers, try to visualize where you see them in your house. It transforms abstract chemistry into a tangible, unforgettable reality!