Monday, May 4, 2015

Synthetic fibres and Plastics

Synthetic fibres and Plastics
Concept Map

Source: NCERT


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  • Fibres which are man-made are called man-made or synthetic fibres. For example – rayon, nylon, acrylic, etc.
  • Synthetic Fibres: Synthetic fibres are small units of chemicals joined together in the form of chain. The chain so formed is called polymer.
  • Types of Synthetic Fibres: Rayon,Nylon,Polyester,Terrycot ( fabric made after mixing of terylene and cotton),PET (Polyethylene terepthalate),Acrylic:
  • Characteristic of Synthetic Fibre
    • Synthetic fibres are cheaper than natural fibre.
    • Synthetic fibres are stronger than natural fibre.
    • Synthetic fibres are more durable than natural fibre.
    • It is easy to maintain the synthetic fibres.
    • It is easy to wash the synthetic fabrics.
    • Synthetic fabrics are dried up in less time.
    • Synthetic fibres are readily available.
    Plastics
    Types of Plastic: Plastic can be divided into two main types – Thermoplastics and Thermosetting.
    Thermoplastic: Plastics which can be easily bent or deform on heating are known as thermoplastic. PVC and Polythene are the examples of thermoplastics. Thermoplastics are used in making toys, bottles, combs, containers, etc.
    Thermosetting plastic: Plastics which do not get deformed or softened on heating when mold once, are called thermosetting plastics. Bakelite and melamine are the examples of thermosetting plastics. Thermosetting plastics are used in making hard board, electric switch, handles
    Characteristics of Plastic : Poor conductor, Plastic is non-reactive, Plastic is 
  • strong and durable
  • Biodegradable and Non-biodegradable:
  • Substances which get decomposed through the natural processes, such as action of bacteria, etc. are called biodegradable substances. For example; potato peels, peels of other vegetable, food stuffs, fruit, paper, cotton cloths, wood, etc.
  • Substances which either do not decompose or take many years to get decomposed through the natural process, are called non-biodegradable substance, e.g. tin, aluminium, plastics, etc.


Preventive measures:
For dealing with the menace of plastic waste, we need to follow the three Rs, i.e. Reduce, Reuse and Recycle.

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