Types of Polymers

Types of Polymers

Thermoplastics

  • Thermoplastics are a type of polymer that become pliable or mouldable above a specific temperature and solidify upon cooling.

  • They are reversible, i.e., they can be reheated, reshaped, and frozen repeatedly.

  • This category includes polymers like polyethylene, polypropylene, polyvinyl chloride (PVC), and polystyrene.

  • Their properties include good strength, low weight, and resistance to moisture and chemicals.

Thermosetting Polymers

  • Thermosetting polymers are different because once they are heated and formed, they can’t be reheated and reformed.

  • They undergo a chemical change when heated, creating a three-dimensional network of bonded molecules.

  • Examples of such polymers include epoxy resin, melamine formaldehyde, and polyester resin.

  • They offer high resistance to heat and chemicals and are used in products that need to maintain their shape, even under extreme conditions.

Elastomers

  • Elastomers are polymers that are highly elastic. They can be stretched significantly and will return to their original shape once the stress is released.

  • They are generally covalently bonded and have weaker intermolecular forces, resulting in lower melting points.

  • Rubber, both natural and synthetic, is a prime example of an elastomer.

  • Elastomers have high tear resistance and rebound capacity and are best suited in applications that require flexibility and elasticity.

Fibre-Reinforced Plastics (FRPs)

  • Fibre-reinforced plastics are composites made from a polymer matrix reinforced with fibres.

  • The combination of the fibres with the plastic provides strength and stiffness that are superior to those of the polymers used alone.

  • There are many types of FRPs, including glass-reinforced plastic (GRP) and carbon fibre-reinforced plastic (CFRP).

  • They exhibit properties such as high strength, low weight, and resistance to heat, corrosion, and weathering, which makes them ideal for use in a wide range of applications.

Remember: Knowing the difference between thermoplastics and thermosetting polymers is especially important, as it impacts their processing and recycling capabilities. Understanding the unique properties of each type of polymer will enable you to choose the appropriate material for a given project.