Crystal

Polymerisation Reactions

polymers

Classification of Polymers

CBSE Class 12 Chemistry Chapter 15 Revision Notes

Many manufactured materials, including us humans, are made up of polymers. So let's get to know them well in this guide!

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Chapter 15: Polymers Revision Notes

  • A polymer is a large molecule with a high molecular mass that is made up of many small molecules called monomers that are repeatedly bonded together.
  • Polymerisation is the process by which monomers are converted into polymers.
  • Polymers are also known as macromolecules because they are single large molecules.

Classification of Polymers

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Polymerisation Reactions

  • Addition polymerisation, also known as chain growth polymerisation, is a polymerization process in which monomers with one or more double bonds are added in a chain fashion in the presence of an initiator to form a polymer. The free radical mechanism is in charge of it.
  • Step growth polymerisation or condensation polymerisation: It happens when monomers condense in a stepwise manner, removing water or other small molecules along the way.
  • Copolymerisation: A copolymer is formed when a mixture of more than one monomeric species polymerizes. A copolymer is a polymeric chain that contains multiple units of each monomer. Styrene and methacrylate, for example, form a copolymer.
  • Cis 1,4-polyisoprene is a type of natural rubber. It's an isoprene 1,4-polymer with a linear structure. Rubber latex, which is a colloidal suspension of rubber in water, is used to make it.
  • Vulcanisation of rubber is the process of heating a mixture of raw rubber and sulfur between 373 and 415 degrees Celsius. Adding additives like ZnO to the vulcanisation process speeds it up.
  • Biodegradable polymers: PHBV and Nylon 2- Nylon-6 were created to reduce the environmental risks associated with synthetic polymeric waste.