What chemical substance constitutes the primary ingredient of natural rubber_________________?
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Answer: B. Polyisoprene
Explanation
Natural rubber is an elastomer whose primary chemical building block is cis-polyisoprene. Latex sap harvested from rubber trees consists of stable colloidal dispersions containing polyisoprene macromolecules. The correct option specifies polyisoprene as the fundamental chemical constituent forming natural rubber elastomers. Polyisoprene is a polymer formed from repeating isoprene monomer units joined in a specific cis stereochemical configuration. The cis geometry coils the polymer chains, allowing them to stretch extensively and snap back upon release. Natural rubber exhibits remarkable elasticity, resilience, and flexibility at ambient room temperatures.
Automobile tire manufacturing consumes substantial amounts of natural rubber to provide superior grip and heat dissipation. Medical devices such as surgical gloves and tubing rely on natural polyisoprene for flexibility and tactile sensitivity. Understanding elastomer chemistry allows scientists to develop synthetic equivalents that mimic natural rubber performance. Option A is polystyrene which is a rigid, brittle thermoplastic used for disposable containers, not an elastomer. Option C is polybutadiene, a synthetic rubber produced from butadiene monomers rather than natural isoprene units. Option D is polychloroprene, also known as neoprene, which is an artificial synthetic rubber containing chlorine.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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