Page 27 - Science Class 08
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Materials in Daily Life
• Materials : Natural and Man-made • Synthe c Fibres • Rayon • Nylon
• Polyester • Need for Synthe c Materials • Polymerisa on • Plas cs
We use a number of materials in our daily life. that occur in the nature naturally are called
Some of these such as wood, co on, stones natural materials.
and clay are natural materials. However, most For example, wood, stones, coal, crude oil, iron,
of the materials we see around us do not occur air, water, co on, jute, etc.
as such in nature. They have been changed
On the other hand, there are many materials
from their natural state by chemical processes. which have been changed from their natural
Plas cs, paints, medicines, cement, fer lizers
state by chemical processes. These materials
and synthe c fibres are some such human-
are called man-made materials.
made materials. These materials are made from
raw materials such as coal, crude oil, natural For example, plas cs, paints, synthe c fibres,
medicines, fer lizers, etc.
gas, air, water, salt and limestone. Chemical
processes are used to change these raw In this chapter, you will study about man-made
materials into materials with special proper es fibres called synthe c fibres and plas cs.
which we can use for specific purposes. In previous class, you have studied about some
Human-made materials are made in factories natural fibres like co on, jute, silk and linex.
called industrial plants. Raw materials are Co on, jute and linex are obtained from co on,
converted into useful materials by chemical jute and flax plants, respec vely. Silk is
reac ons. The human-made materials industry obtained from silkworms. Co on and silk fibres
is one of the largest industries in the world are used to make fabric while jute is used to
today. make gunny bags, doormats, etc.
MATERIALS : NATURAL AND MAN-MADE SYNTHETIC FIBRES
Now, you know that all the objects we use are The common natural fibres used for making
made up of one material or the other. Where cloth are wool, co on and silk. They are
do these materials come to us from? Materials obtained from plants and animals. They are
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