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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
Fill in the blanks with appropriate words.
Like synthetic fibres, plastic is also a _______
Explain why the following is made of thermosetting plastics.
Saucepan handles
Write the natural or manmade raw material of the following items.
Mattress, glass vessel, bangle, chair, gunny bag, broom, knife, pen.
Can you replace the following packaging material with those which can be recycled or reused.
Gift items packed with shiny material.
PVC (polyvinyl chloride) is a thermoplastic and is used for making toys, chappals, etc. Bakelite is a thermosetting plastic and is used for making electrical switches, handles of various utensils, etc. Can you write the major difference between these two types of plastics?
A survey showed that one-time-use plastic items were among the top 10 plastic items found in garbage washed up from oceans. Can this be true? Explain how.
Pet name for Buckminster Fullerene is ______.
Answer the following by rearranging the jumbled letters :
Plastics made of _______ are represented by resin code #6.
sytlopynere
Answer the following by rearranging the jumbled letters :
One-time use of plastics causes ______ damage.
trnvomenialne
Give some examples of one-time-use plastic.
