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Question
How the plastic is produced?
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Solution
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).
RELATED QUESTIONS
Write uses of PVC.
Write the natural or manmade raw material of the following items.
Mattress, glass vessel, bangle, chair, gunny bag, broom, knife, pen.
Distinguish between.
Man made material and natural material.
Write short note.
Glass production.
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What are the uses of plastic?
Read the following information and convert them into a graph to compare the countries and the amount of plastic they use.
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Plastic articles are available in all possible shapes and sizes. Can you tell why?
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?
Assertion (A): PVC is an unsafe plastic.
Reason (R): Burning PVC releases dioxins, a most toxic chemical.
