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प्रश्न
Write preparation of low density polythene.
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उत्तर
Preparation of low density polythene:
- 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.
\[\ce{{n} CH2 = CH2 ->[Traces of O2 or][peroxide at 350–570 K, 1000–2000 atm] LDP}\] - The mechanism of this reaction involves free radical addition and H-atom abstraction. The latter results in branching.
- Polymeric chains are loosely held due to branching and the polymer has low density.
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संबंधित प्रश्न
Explain the following term: Homopolymers
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(a) Benzaldchyde and phenol
(b) Acetaldehyde and phenol
(c) Formaldehyde and phenol
(d) Formaldehyde and benzyl alcohol
Choose the correct option from the given alternatives.
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Answer the following in one sentence.
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Answer the following.
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Answer the following.
Write the reaction of the formation of Terylene.
Answer the following.
Match the following pairs:
| Name of polymer | Monomer |
| 1. Teflon | a. CH2 = CH2 |
| 2. PVC | b. CF2 = CF2 |
| 3. Polyester | c. CH2 = CHCl |
| 4. Polythene | d. C6H5OH and HCHO |
| 5. Bakelite | e. Dicarboxylic acid and polyhydoxyglycol |
Answer the following.
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H2N–(CH2)5 – COOH
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-(CO(CH2)4 - CONH(CH2)6NH-)n
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a. Neoprene
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| Polymer | Monomer | ||
| (i) | Teflon | (a) | CH2 = CH2 |
| (ii) | PVC | (b) | CF2 = CF2 |
| (iii) | Natural rubber | (c) | Isoprene |
| (iv) | Polythene | (d) | H2C=CHCl |
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Write the structure of isoprene and the polymer obtained from it.
Write the structure of isoprene and the polymer obtained from it.
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Name and draw structure of the repeating unit in natural rubber.
Write the structure of isoprene and the polymer obtained from it.
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