Neoprene production — The monomer used to produce neoprene rubber is:
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AChloroethane (ethyl chloride)
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BChloroprene (2-chloro-1,3-butadiene)
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CIsoprene (2-methyl-1,3-butadiene)
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DVinyl chloride (chloroethene)
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EButadiene (1,3-butadiene)
Answer
Correct Answer: Chloroprene (2-chloro-1,3-butadiene)
Explanation
Introduction / Context:Linking elastomer trade names to their monomers clarifies structure–property relationships. Neoprene is prized for oil and weather resistance; this originates from the chlorine substituent on its diene monomer.
Given Data / Assumptions:
- We identify the specific monomer for neoprene.
- Common conjugated dienes and halo-derivatives are listed.
Concept / Approach:Neoprene is polychloroprene formed by the polymerization of chloroprene (2-chloro-1,3-butadiene). The presence of chlorine provides enhanced oxidative and oil resistance relative to polyisoprene or polybutadiene elastomers.
Step-by-Step Solution:Match name: neoprene ↔ polychloroprene.Thus, the monomer must be chloroprene.Therefore, choose chloroprene.
Verification / Alternative check:Polymer references and manufacturer datasheets consistently define neoprene as polychloroprene made from chloroprene.
Why Other Options Are Wrong:
- Chloroethane, vinyl chloride: produce different polymers (e.g., PVC from vinyl chloride).
- Isoprene: yields natural rubber equivalent (polyisoprene).
- Butadiene: yields polybutadiene or SBR when copolymerized with styrene.
Common Pitfalls:Confusing chloroprene with vinyl chloride or isoprene due to similar names; forgetting the necessity of the conjugated diene structure.
Final Answer:Chloroprene (2-chloro-1,3-butadiene)