Natural Polymers, Examples, Properties, Some Polymers and Their Monomers (For CBSE, ICSE, IAS, NET, NRA 2022)

Doorsteptutor material for competitive exams is prepared by world's top subject experts: get questions, notes, tests, video lectures and more- for all subjects of your exam.

Types of Polymerization Reactions

Addition Polymerization

This is also called as chain growth polymerization. In this, small monomer units joined to form a giant polymer. In each step length of chain increases. For example, Polymerization of ethane in the presence of Peroxides

Condensation Polymerization

In this type small molecules like are eliminated during polymerization (step growth polymerization) . Generally, organic compounds containing bifunctional groups such as idols, -dials, diamines, dicarboxylic acids undergo this type of polymerization reaction. For example, Preparation of nylon -6,6.

What is Copolymerization?

In this process, two different monomers joined to form a polymer. Synthetic rubbers are prepared by this polymerization. For example, BUNA – S.

Uses of Polymers

Here we will list some of the important uses of polymers in our everyday life.

  • Polypropene finds usage in a broad range of industries such as textiles, packaging, stationery, plastics, aircraft, construction, rope, toys, etc.
  • Polystyrene is one of the most common plastic, actively used in the packaging industry. Bottles, toys, containers, trays, disposable glasses and plates, tv cabinets and lids are some of the daily-used products made up of polystyrene. It is also used as an insulator.
  • The most important use of polyvinyl chloride is the manufacture of sewage pipes. It is also used as an insulator in the electric cables.
  • Polyvinyl chloride is used in clothing and furniture and has recently become popular for the construction of doors and windows as well. It is also used in vinyl flooring.
  • Urea-formaldehyde resins are used for making adhesives, moulds, laminated sheets, unbreakable containers, etc.
  • Glyptal is used for making paints, coatings, and lacquers.
  • Bakelite is used for making electrical switches, kitchen products, toys, jewellery, firearms, insulators, computer discs, etc.

Questions

How Do Polymers Have Different Physical Properties? Give Examples

Answer:

In polymers, monomers are bonded, by different molecular interactions. Nature of these interactions, yield polymers of varying elasticity, tensile strength, toughness, thermal stability, etc.

  • Monomers forming a linear chain with weak bonding. These polymers exhibit elasticity and are called elastomers. Example: Neoprene, Buna-S, Buna-R.
  • Polymers with strong forces of interaction between the monomer in both linear and between the chains have higher tensile strength and are used as fibres. Example: Polyamides (nylon 6,6) , polyesters (terylene) .
  • Polymers having their intermolecular force in between the elastomers and fibres are thermoplastics. They can be repeatedly reprocessed without much change in their polymeric properties. Example: Polythene, polyvinyl.
  • Monomers that undergo heavy branching, gets fused on heating and cannot be reused or reprocessed. Such materials are thermosetting plastics. Bakelite, Urea-formaldehyde are examples.

What is the Vulcanization of Rubber?

Answer:

Natural rubber is highly elastic to be of poor physical stability. Addition of 5 % of Sulphur, enhances the crosslinking of the linear chains and thus improves the stiffening of the rubber for an application like vehicle tires.

Developed by: