Refrigerator parts and transistor housings are commonly fabricated from_____________________?
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Answer: A. Polystyrene
Explanation
Polystyrene exhibits excellent moldability and rigidity, making it ideal for forming complex interior refrigerator components. The polymer can be rapidly shaped into smooth, seamless inner liners that resist food acids and moisture. Transistor housings also benefit from the electrical insulating properties and lightweight nature of molded polystyrene. Polystyrene is a thermoplastic derived from petroleum that becomes easily deformable when heated above its glass transition temperature. High-impact polystyrene incorporates butadiene rubber to prevent brittleness in thin-walled manufactured housings. Injection molding technology allows manufacturers to produce intricate electronic casings quickly and economically.
Refrigeration units require durable plastic liners that maintain structural integrity at low operating temperatures. Consumer electronics rely on sturdy polymer housings to protect internal circuitry from dust and physical impact. Choosing the right thermoplastic ensures product longevity and reliable performance in everyday household appliances. Polyester resins are typically thermosetting materials or fiber formers rather than standard refrigerator housing plastics. High density polyethylene is exceptionally tough but lacks the crystal clarity and rigidity typical of polystyrene parts. Polyurethane is primarily foamed into thermal insulation panels rather than rigid structural appliance housings.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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