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What is the structural difference between low density poly(ethene) and high density poly(ethene)? - Leaving Cert Chemistry - Question A - 2012
Question A
What is the structural difference between low density poly(ethene) and high density poly(ethene)?
Worked Solution & Example Answer:What is the structural difference between low density poly(ethene) and high density poly(ethene)? - Leaving Cert Chemistry - Question A - 2012
Step 1
Low density poly(ethene)
Answer
Low density poly(ethene) (LDPE) is characterized by its branched structure. The branching creates spaces between the polymer chains, resulting in a more flexible and less dense material. This branching increases the free volume in the polymer, allowing for greater movement of the chains, which contributes to its overall lower density.
Step 2
High density poly(ethene)
Answer
High density poly(ethene) (HDPE), on the other hand, has very little or no branching. The polymer chains are more linear, allowing them to pack closely together with little space between chains. This results in a denser material with higher tensile strength and rigidity compared to LDPE. Additionally, the longer chains in HDPE result in a more crystalline structure.