In wet spinning, polymer solutions are extruded through spinnerets into a coagulation bath. This technique is not employed for _____________ fibres?
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Answer: D. Saturated polyester
Explanation
Saturated polyesters like Dacron are typically spun using melt spinning rather than wet spinning. Melt spinning extrudes the molten polymer directly through spinnerets into cooling air. Wet spinning is reserved for polymers that decompose before melting or require solvent baths. Wet spinning extrudes polymer solutions into a chemical coagulation bath to precipitate fibers. Saturated polyesters possess stable melting points well below their thermal decomposition threshold. Melt spinning is more economical and faster for thermoplastic polymers than solvent techniques.
Textile manufacturing plants produce polyester staple fibers efficiently using melt extrusion. Synthetic fiber production relies on matching the spinning technique to the polymer thermal properties. It matters in industrial processing to choose methods that minimize solvent recovery costs. Viscose rayon is produced using wet spinning because cellulose derivatives require solution processing. Acrylic fibers are commonly manufactured via wet or dry spinning from solvent solutions. Polyvinyl acetate can also involve solution processes, making saturated polyester the correct exception.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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