The polymer used in making car rear lights is

Analysis

The question asks for the specific type of polymer used in the manufacturing of car rear lights. This requires knowledge of the properties and common industrial applications of various synthetic polymers.

Concept Explanation

To solve this, we look at the characteristics of the polymers listed:

• Perspex (Polymethyl methacrylate - PMMA): This is a transparent, rigid, and durable thermoplastic. Because of its high optical clarity and resistance to weathering, it is widely known as "acrylic glass." It is the standard material used for lenses, car rear lights, and windshields.
• Bakelite (Phenol-formaldehyde resin): This is a thermosetting plastic. It is opaque, hard, and heat-resistant, commonly used for electrical fittings like switch plates and handles for cooking pots.
• Polystyrene: This is a versatile plastic used for making disposable cups, food containers, and packaging materials (like Styrofoam). It is generally not used for car lights because it is not as durable or weather-resistant as PMMA.
• Polyacrylonitrile (PAN): This is primarily used in the production of synthetic fibers (like acrylic wool) for clothing and carpets.

Step-by-Step Solution

1. Identify the requirement: Car rear lights need to be transparent, shatter-resistant, and able to withstand outdoor environmental conditions (sunlight and rain).
2. Evaluate the options: • Bakelite is opaque (not suitable for lights). • Polyacrylonitrile is used for fibers (not suitable for rigid light casings). • Polystyrene is brittle and lacks the necessary optical clarity and weather resistance for automotive exterior use. • Perspex (PMMA) is specifically engineered for high transparency and strength, making it the ideal material for automotive lighting.
3. Conclusion: Based on the properties of these polymers, Perspex is the correct material used for car rear lights.

Exam Tip

When dealing with polymer questions in JAMB, remember the "Big Three" applications:

• Perspex: Transparent, glass-like (lights, windows).
• Bakelite: Heat-resistant, electrical insulator (switches, handles).
• Polythene/Polystyrene: Packaging and containers.