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Write preparation of low density polythene. - Chemistry

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Write preparation of low density polythene.

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Solution

Preparation of low density polythene:

  1. LDP is prepared by polymerization of ethylene under high pressure (1000 – 2000 atm) and temperature (350 – 570 K) in presence of traces of O2 or peroxide as initiator.
    \[\ce{{n} CH2 = CH2 ->[Traces of O2 or][peroxide at 350–570 K, 1000–2000 atm] LDP}\]
  2. The mechanism of this reaction involves free radical addition and H-atom abstraction. The latter results in branching.
  3. Polymeric chains are loosely held due to branching and the polymer has low density.
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Chapter 15: Introduction to Polymer Chemistry - Short Answer Questions (Type-I)

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SCERT Maharashtra Chemistry [English] 12 Standard HSC
Chapter 15 Introduction to Polymer Chemistry
Short Answer Questions (Type-I) | Q 5.1

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