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Polyvinyl alcohol.

Polyvinyl alcohol.

  • Polyvinyl alcohol, also known as PVOH,PVA is a synthetic polymer.
  • Polyvinyl alcohol is a unique polymer because it is not build up in the polymerisation reaction from monomers. Instead, Polyvinyl alcohol is made by dissolving another polymer, polyvinyl acetate in an alcohol such as methanol and treating it with an alkaline catalyst such as sodium hydroxide.
    This image shows synthesis of Polyvinyl alcohol from Polyvinyl acetate.
    Polyvinyl alcohol.
  • Polyvinyl alcohol is an odourless and tasteless, translucent, white- cream coloured granular powder.
  • Polyvinyl alcohol has excellent film forming, emulsifying and adhesive properties.
    This image shows types of emulsion; permanent emulsion and temporary Emulsion.
    Emulsion.
  • It is also resistant to oil, grease and solvents.
  • It has high tensile strength and flexibility.
  • It is soluble in water.
  • Polyvinyl alcohol is used in eye drops.
  • Polyvinyl alcohol is used in sizing agents.
  • It is also used as a component of adhesives and emulsifiers.
  • Polyvinyl alcohol is used in contact lenses.
    This image shows uses of Polyvinyl alcohol in eye drops, contact lenses, adhesives.
    Uses of Polyvinyl alcohol.

Questions on Polyvinyl alcohol

Q1) What is Polyvinyl alcohol?
Ans) Polyvinyl alcohol is a synthetic polymer. It is also known as PVOH, PVA.
Q2) How is Polyvinyl alcohol prepared?
Ans) Polyvinyl alcohol is a unique polymer because it is not build up in polymerisation reactions from monomers. Instead, Polyvinyl alcohol is made by dissolving another polymer, Polyvinyl acetate in an alcohol such as methanol and treating it with an alkaline catalyst such as sodium hydroxide.
Q3) What is emulsion?
Ans) Emulsion is a mixture of two liquids that ordinary do not combine, such as oil and water. When stirred or shaken vigorously, two liquids will form a temporary emulsion. Within a relatively short time, however, the two will seperate into distinct layers. A permanent emulsion can be made by adding a third substance called an emulsifier. Oil and water will form a permanent emulsion if soap or detergent is added as an emulsifier.
Q4) Write some properties of Polyvinyl alcohol?
Ans) Some properties of Polyvinyl alcohol are given below;
1) Polyvinyl alcohol is an odourless and tasteless, translucent, white or cream coloured granular powder.
2) Polyvinyl alcohol has excellent film forming, emulsifying and adhesive properties.
3) It is also resistant to oil, grease and solvents.
4) It has high tensile strength and flexibility.
5) It is soluble in water.
Q5) Write some uses of Polyvinyl alcohol?
Ans) Some uses of Polyvinyl alcohol are given below;
1) Polyvinyl alcohol is used in eye drops.
2) Polyvinyl alcohol is used in sizing agents.
3) It is also used as a component of adhesives and emulsifiers.
4) Polyvinyl alcohol is used in contact lenses. Next

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