Question
Write preparation of low density polythene.
✓
Answer
Preparation of low density polythene:
(a) LDP is prepared by polymerization of ethylene under high pressure $(1000 – 2000\ atm)$ and temperature $(350 – 570\ K)$ in presence of traces of $O_2$ or peroxide as initiator.
(b) The mechanism of this reaction involves free radical addition and $H-atom$ abstraction. The latter results in branching.
(c) Polymeric chains are loosely held due to branching and the polymer has low density.
(a) LDP is prepared by polymerization of ethylene under high pressure $(1000 – 2000\ atm)$ and temperature $(350 – 570\ K)$ in presence of traces of $O_2$ or peroxide as initiator.
(b) The mechanism of this reaction involves free radical addition and $H-atom$ abstraction. The latter results in branching.
(c) Polymeric chains are loosely held due to branching and the polymer has low density.
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