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Buna S or styrene butadiene rubber (SBR).

Buna S or styrene butadiene rubber (SBR).

  • In Buna S, Bu stands for butadiene and, Na stands for sodium and S stands for styrene.
  • Styrene and butadiene are the monomers of Buna-S rubber.
  • It is a co-polymer formed by the emulsion polymerisation of a mixture of butadiene and styrene in the presence of peroxide catalyst.
    This image contains formation of Buna S or styrene butadiene rubber from monomers styrene and butadiene.
    Buna S.
  • The rubber obtained is also called styrene butadiene rubber (SBR) or GR-S rubber.
  • It is a type of synthetic rubber.
  • It has good abrasion resistance.
  • It is very tough and a good substitute for natural rubber.
  •  It swells in organic solvents upto limited extend.
  • It gets oxidised in the presence of traces of ozone.
  • It is widely used in shoe soles and even in chewing gums.
  • It is used to make car tyres, floor tiles.
  • It is also used as adhesives.
    This image shows uses of Buna-S or SBR as adhesives,shoe soles, chewing gum,car tyres,floor tiles.
    Uses of Buna S.

Questions on Buna S

Q1) What is Buna S?
Ans) Buna S is a synthetic rubber. Styrene and butadiene are the monomers of Buna-S rubber.
Q2) What are the monomers of Buna-S?
Ans) Styrene and butadiene are the monomers of Buna-S.
Q3) How is Buna S prepared?
Ans) It is a copolymer formed by the emulsion polymerisation of a mixture of butadiene and styrene in the presence of peroxide catalyst.
Q4) Write some properties of Buna-S?
Ans) Some properties of Buna-S are given below;
1) It has good abrasion resistance.
2) It is a type of synthetic rubber.
3) It is very tough and a good substitute for natural rubber.
4) It gets oxidised in the presence of traces of ozone.
5) It swells in organic solvents upto limited extend.
Q5) Write some uses of Buna-S?
Ans) Some uses of Buna S are given below;
1) It is used widely in shoe soles and even in chewing gums.
2) It is used to make car tyres, floor tiles.
3) It is also used as adhesives.
Q6) Buna S is also known as?
Ans) Buna S is also known as styrene butadiene rubber (SBR) or GR-S rubber. Next


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