PSEB 8th Class Science Notes Chapter 3 Synthetic Fibres and Plastics

This PSEB 8th Class Science Notes Chapter 3 Synthetic Fibres and Plastics will help you in revision during exams.

PSEB 8th Class Science Notes Chapter 3 Synthetic Fibres and Plastics

→ Clothes are made of fabrics.

→ Fabrics are made by using fibres.

→ Fibers can be obtained from natural or artificial sources.

→ Synthetic fibres are also known as man-made or artificial fibres.

PSEB 8th Class Science Notes Chapter 3 Synthetic Fibres and Plastics

→ Synthetic or natural fibres are chains of small units joined together. Long chains are called polymers.

→ Cellulose is a natural polymer.

→ Rayon, Nylon, Polyester, or Acrylic are man-made fibres.

→ The Source of natural fabric (cotton, silk, etc.) is plants or animals.

→ The Source of artificial fabric is either plants (wood) or fossil fuels (coal etc).

→ Nylon was the first fully synthetic fibre.

→ Different fabrics have different strengths, water holding capacities, cost, durability, availability, and maintenance requirements.

→ Plastics are also polymers having different types of arrangement of units.

→ Plastics are of two types:

  • Thermoplastics
  • Thermosetting plastics

→ Polythene is a type of plastic.

→ Plastic is a light, strong, durable, non-corrosive, poor conductor of electricity and heat.

→ Plastic waste is not environmentally friendly. It is non-biodegradable.

PSEB 8th Class Science Notes Chapter 3 Synthetic Fibres and Plastics

→ On burning, it produces harmful gases and a bad odour.

→ Dumping in the soil makes the soil barren because it does not decompose quickly.

→ 4R principle (Reduce, Reuse. Recycle and Recover) must be used for the disposal of synthetic waste.

→ Man-made Fibres: The fibres made by human beings are called man-made fibres.

→ Polymer: A large unit made up of a chain of smaller units of chemical substances or a large unit made up of many repeating units.

→ Rayon: A synthetic fibre having properties of silk and is also known as artificial silk.

→ PET: A familiar form of polyester used for making bottles, films, ropes, and utensils, etc.

→ Thermoplastic: A type of plastic that gets deformed on heating and can be bent easily is known as thermoplastic.

→ Thermosetting Plastic: A plastic that does not get deformed on heating is called thermosetting plastic. It can be moulded only once.

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