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प्रश्न
How the plastic is produced?
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उत्तर
Plastics are derived from natural, organic materials such as cellulose, coal, natural gas, salt and of crude oil. Crude oil is a complex mixture of thousands of compounds. The production of plastics begins with the distillation of crude oil in an oil refinery. This separates the heavy crude oil into groups of lighter components, called fractions. Each fraction is a mixture of hydrocarbon chains, which differ in terms of the size and structure of their molecules.
Two main processes are used to produce plastics - polymerisation and polycondensation. In a polymerisation reaction, monomers such as ethylene and propylene are linked together to form long polymer chains. In a polycondensation reaction, different monomer units are linked together to form long polymer chains. Each polymer has its own properties, structure and size depending on the nature of monomer different quality plastics are produced.
There are many different types of plastics, and they can be grouped into two main polymer families:
- Thermoplastics (which soften on heating and then harden again on cooling).
-
Thermosets (which never soften once they have been moulded).
संबंधित प्रश्न
Explain why plastic containers are favoured for storing food.
Explain the difference between thermoplastic and thermosetting plastics.
Give examples to show that plastics are non-corrosive in nature.
Who is my partner?
| 'A' column | 'B' column |
| a. Lead glass | i. Plates |
| b. Bakelite | ii. Mattresses |
| c. Thermocol | iii. Electric bulb |
| d. Optic glass | iv. Electric switch |
| e. Polypropylene | v. Lens |
Write uses of PVC.
Distinguish between.
Man made material and natural material.
Can you replace the following packaging material with those which can be recycled or reused.
Dry eatables in polythene.
HOTS
The Tamil Nadu Government has banned the use of one-time use throwaway plastics. Why do you think this is important?
Plastic articles are available in all possible shapes and sizes. Can you tell why?
Answer the following by rearranging the jumbled letters :
Expanded polystyrene is commercially known as ______.
mthreolco
