Skip to main content

Buna N or Nitrile rubber.

Buna N or Nitrile rubber;

  • Bu stands for butadiene, Na stands for sodium and N stands for ethylene nitrile.
  • Nitrile rubber, also known as NBR, Buna-N, GR-N and acrylonitrile butadiene rubber, is a synthetic rubber.
  • It is prepared by the copolymerisation of 1,3-butadiene and acrylonitrile.
    This image shows synthesis of Buna N from butadiene and acrylonitrile.
    Buna N.
  • It is a copolymer of butadiene and acrylonitrile.
  • It possesses extraordinary resistance to oils, acids, salts, heat, abrasion and sunlight.
  • It is less resistant to alkalies.
  • It swells in organic solvents to a certain limit.
  • It is used for making fuel tanks, gasoline hoses, conveyor belts.
  • It is used as adhesives.
  • It is also used to make automobile parts, high altitude air craft components.
This image shows uses of Buna N in making adhesives, fuel tanks, gasoline hoses, conveyor belts.
Uses of Buna N.

Questions on Buna N

Q1) What is Buna N?
Ans) Buna N is a synthetic rubber. It is a copolymer of butadiene and acrylonitrile.
Q2) What are the monomers of Buna N?
Ans) 1,3-Butadiene and acrylonitrile are the monomers of Buna N.
Q3) How is Buna N prepared?
Ans) It is prepared by the polymerisation of 1,3-butadiene and acrylonitrile.
Q4) Write some properties of Buna N?
Ans) Some properties of Buna N are given below;
1) It possesses extraordinary resistance to oils, acids, salts, heat, abrasion and sunlight.
2) It has less resistant to alkalies.
3) It swells in organic solvents to a certain limit.
Q5) Write some uses of Buna N?
Ans) Some uses of Buna N are given below;
1) It is used for making fuel tanks, gasoline hoses, conveyor belts.
2) It is used as adhesives.
3) It is also used to make automobile parts, high altitude air craft components. Next


Comments

Popular posts from this blog

Determination of molecular weight of polymers by viscosity method.

Determination of molecular weight of polymers by viscosity method. It is a simple method for determining the molecular weight of polymers. Addition of polymers in the solvent increases the viscosity of the solvent, due to introduction of inhomogeneities by the polymers. If η₀ is the viscosity of the solvent and η is the viscosity of the solution at the same temperature, then the relative viscosity is given by Relative viscosity. Specific viscosity:  It is defined as the relative increase in viscosity and is given as Specific viscosity. Reduced viscosity: It is defined as the relative increase in viscosity per unit concentration (C) of polymer and is given as Reduced viscosity. Intrinsic viscosity: The reduced viscosity is dependent on concentration (C). If a graph is plotted between  reduced viscosity vs concentration then the extraplotation value when C=0 is called intrinsic viscosity. Intrinsic viscosity. Graph of reduced viscosity vs concentr

Determination of molecular weight by Light scattering method.

Determination of molecular weight by Light scattering method. Due to big size macromolecules in solution, turbidity is produced. The light rays get scattered, when pass through macromolecule solution due to turbidity. The turbidity T is given by Where I₀ is the intensity of incident light. Iₜ is the intensity of transmitted light after passing through a solution of length l.        In case of proteins or higher polymers the turbidity is small and is determine from the intensity of light scattered at 90° to the beam. This can be done by using a simple photometer as shown in figure below. Turbidity increase with increase in concentration as well as molecular weight. The Turbidity is related to molecular weight by the equation given by Debye. Hc/T=1/M+2Bc Where B is second virial coefficient and H is a constant. If we plot a graph between Hc/T vs c we get a straight line with intercept 1/M. Thus This curve was plotted by Zimm, so is called Zimm's Curve. Thus the c

Kinetics of copolymerisation and Composition of copolymer.

Kinetics of copolymerisation and Composition of copolymer. We must know that Where r₁ and r₂ are the reactivity ratio's for the given pair of monomers. Where the above equation is called Copolymerisation equation and it gives the copolymerisation composition without using radical concentration. Types of copolymerisation ( kinetics significance) Let us take the reactivity ratio's product of monomers i.e Product of reactivity ratios. Depending on whether this product is less, greater or equal to unity copolymers are divided into three types. 1)Ideal copolymerisation Here the product of reactivity ratios is equal to unity, i.e r₁r₂=1 2) Alternating copolymerisation Here the product of reactivity ratios is equal to zero, i.e r₁r₂=0. 3)Block copolymerisation Here the product of reactivity ratios is greater than 1, i.e r₁r₂>1.