Natural rubber (Polyisoprene).

Natural rubber (Polyisoprene)

Polyisoprene (polymer of isoprene) is the primary chemical constituent of natural rubber.
Thus isoprene is a monomer of natural rubber.

Polyisoprene.
Natural rubber is soft and sticky.
It has elasticity.
It can be used over a narrow range of temperature (from 10°C to 60°C).
Natural rubbers are sensitive to heat.
Natural rubbers are easily oxidised by air.
It is insoluble in water.
It is soluble in solvents like ether, carbon tetrachloride, petrol etc.
Natural rubbers are used to make rubber bands.
They are also used to make shoe soles and rubber tubes.
They are used to make gloves, erasers, mats etc. Next

Uses of natural rubber.

Questions on polyisoprene;
Q1) What is polyisoprene?
Ans) Polyisoprene (polymer of isoprene) is the primary chemical constituent of natural rubber.
Q2) What is the monomer of polyisoprene?
Ans) Isoprene is the monomer of polyisoprene.
Q3) Write some properties of polyisoprene?
Ans) Some properties of polyisoprene are given below;
1) It is soft and sticky.
2) It has elasticity.
3) It can be used over a narrow range of temperature (from 10°C to 60°C).
4) It is insoluble in water.
5) Polyisoprene are easily oxidised by air.
6) Polyisoprene are sensitive to heat.
7) It is soluble in solvents like ether, carbon tetrachloride, petrol etc.
Q4) Write some uses of polyisoprene?
Ans) Some uses of polyisoprene are given below;
1) Polyisoprene are used to make rubber bands.
2) They are also used to make shoe soles and rubber tubes.
3) They are used to make gloves, erasers, mats etc.

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