Identify the monomer used to produce neoprene (polychloroprene) synthetic rubber in commercial practice.
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AAcetylene
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BChloroprene (2-chloro-1,3-butadiene)
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CIsoprene (2-methyl-1,3-butadiene)
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DNone of these
Answer
Correct Answer: Chloroprene (2-chloro-1,3-butadiene)
Explanation
Introduction / Context:Neoprene is the trade name for polychloroprene, a versatile synthetic rubber noted for oil resistance, weathering resistance, and good mechanical strength. Knowing its monomer origin clarifies performance attributes and processing behaviour.
Given Data / Assumptions:
- The polymer family is polychloroprene.
- We pick the correct monomer from common diene candidates.
Concept / Approach:Polychloroprene is formed by polymerising chloroprene (2-chloro-1,3-butadiene). Although acetylene chemistry historically featured in early monomer syntheses (e.g., for chloroprene manufacture), acetylene is not the monomer polymerised to form neoprene. Isoprene polymerises to natural rubber-like polyisoprene, not neoprene.
Step-by-Step Solution:Match trade name to chemical family: neoprene → polychloroprene.Identify the exact monomer: chloroprene.Exclude other dienes that yield different rubbers.
Verification / Alternative check:Rubber technology texts list chloroprene emulsion polymerisation as the standard route to neoprene.
Why Other Options Are Wrong:Acetylene: feedstock/intermediate for various chemicals, not the final monomer here.Isoprene: monomer for polyisoprene (natural/synthetic), not neoprene.None: incorrect; a specific correct monomer exists.
Common Pitfalls:Confusing raw feedstocks (used upstream) with the actual polymerised monomer.
Final Answer:Chloroprene (2-chloro-1,3-butadiene)