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Polyurethane.

Polyurethane (PUR or PU).

  • Polyurethane (PUR or PU) is a polymer composed of organic units joined by carbamate (urethane) links.
  • Polyurethane polymers are traditionally and most commonly formed by reacting diisocyanate with polyol. A linear polyurethane is produced by condensation polymerisation of a diol and a diisocyanate in the presence of suitable catalyst and additives. 
    Synthesis of polyurethane from diisocyanate and diol.
    Polyurethane.
  • Sometimes instead of using a small diol like ethylene glycol, we use polyethylene glycol.
This image shows polyethylene glycol.
Poly(ethylene glycol).
  • The properties of PURs greatly depend on the structure of the polymer backbone. They can be tailored to have high strength, high rigidity or high flexibility and toughness.
  • Most of PURs have good resistance to oil, aromatic hydrocarbons, oxygen and ozone.
  • It is used to make durable elastomeric wheels and tires such as roller coaster wheels, Skateboard wheels.
  • It is used to make high performance adhesives.
  • It is also used to make synthetic fiber like spandex. Spandex is known for its exceptional elasticity.
  • It is used to make shoe soles and sportswear.
  • It is used to make mattresses.
  • It is used in refrigerators and freezers.
    This image shows uses of polyurethane in freezers, refrigerators, mattresses, roller coaster wheels, skateboard wheels, sportswear,shoe soles.
    Uses of Polyurethane.

Questions on Polyurethane;

Q1) What is polyurethane?
Ans) Polyurethane is a polymer composed of organic units joined by carbamate (urethane) links.
Q2) How is polyurethane prepared?
Ans) Polyurethane polymers are traditionally and most commonly formed by reacting diisocyanate with polyol. A linear polyurethane is produced by condensation polymerisation of diisocyanate and diol in the presence of suitable catalyst and additives.
Sometimes instead of using a small diol like ethylene glycol, we use a polyethylene glycol.
Q3) Write some properties of polyurethane?
Ans) Some properties of polyurethane are given below;
1) Most of polyurethanes have good resistance to oil, aromatic hydrocarbons, oxygen and ozone.
2) Polyurethanes are susceptible to microbial attacks.
3) The properties of polyurethanes greatly depend on the structure of the polymer backbone. They can be tailored to have high strength, high rigidity or high flexibility and toughness.
Q4) Write some uses of polyurethane?
Ans) Some uses of polyurethane are given below;
1) It is used to make durable elastomeric wheels and tires such as roller coaster wheels, skateboard wheels.
2) It is used to make high performance adhesives.
3) It is also used to make synthetic fiber like spandex. Spandex is known for its exceptional elasticity.
4) It is used to make shoe soles and sportswear.
5) It is used to make mattresses.
6) It is used in refrigerators and freezers. Next

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