_____________ scrap can be successfully recycled and reused?
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Answer: C. Polythene
Explanation
Polythene is a thermoplastic polymer meaning it softens when heated and can be melted down and recycled. Thermoplastics feature linear or branched polymer chains that do not possess permanent chemical crosslinks. Because polyethylene scrap can be remelted without degradation it is successfully recycled into new products. Polythene or polyethylene is produced by the addition polymerization of ethylene gas monomers. Thermosetting plastics undergo irreversible chemical crosslinking and decompose when reheated instead of melting. Recycling thermoplastic scrap reduces plastic waste and conserves valuable petrochemical resources.
Post-consumer polyethylene packaging and industrial plastic scrap are regularly collected for mechanical recycling. Recycled polythene is processed into agricultural films plastic lumber and various molded containers. Sorting plastic waste by polymer type is essential for maintaining mechanical quality in recycled resins. Bakelite is a thermosetting phenol-formaldehyde resin that chars upon heating and cannot be remelted. Epoxy resins cure into permanently crosslinked networks making them impossible to recycle via melting. Stating none of these is incorrect because polythene is a thermoplastic that is widely recycled.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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