How does polypropylene compare in properties to polyethylene___________________?
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Answer: D. All A., B. and C.
Explanation
Polypropylene possesses a higher crystallinity, making it harder and stronger than polyethylene. Its lower density allows polypropylene to be significantly lighter than standard polyethylene. All these physical property improvements make polypropylene superior in certain applications. Polypropylene is an addition polymer synthesized from propylene monomer gas units. The presence of methyl groups on the polymer chain increases rigidity and melting points. Polyethylene has a simpler chemical structure with higher flexibility and lower hardness.
Hinges and living hinges molded into plastic containers utilize polypropylene fatigue resistance. Automotive battery cases and bumpers benefit from its strength and light weight. Packaging films and woven sacks frequently utilize polypropylene for enhanced durability. Polypropylene is harder than polyethylene, refuting the idea that it lacks hardness. Its tensile strength exceeds standard polyethylene grades used in common packaging. Polypropylene has a lower density than polyethylene, confirming its lighter weight.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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