The Ziegler process__________________?
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Answer: A. Produces high density polyethylene
Explanation
The Ziegler-Natta coordination catalyst system polymerizes ethylene gas under exceptionally mild industrial conditions. Using transition metal halides with organoaluminum co-catalysts produces highly linear polyethylene chains. Linear polymer chains pack closely together, yielding a high-density product with superior rigidity. Karl Ziegler and Giulio Natta won the Nobel Prize for discovering stereospecific polymerization catalysts. High-density polyethylene features minimal branching, leading to strong intermolecular forces and high crystallinity. Coordination polymerization allows precise control over polymer architecture and molecular weight distribution.
High-density polyethylene is widely used for manufacturing rigid containers, pipes, and structural components. Global packaging industries consume millions of tons of this polymer annually for durability. Understanding catalytic polymerization enables engineers to design materials with tailored mechanical properties. Low density polyethylene is produced via free-radical polymerization requiring extremely high pressures. Ziegler processes explicitly require active transition metal catalysts to function efficiently. Operating pressures in Ziegler processes are typically very low compared to older radical methods.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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