This document discusses natural and synthetic fibers and different types of plastics. It provides details on thermoplastics and thermosetting plastics. Plastics are described as poor conductors of heat and electricity, non-reactive, strong and durable. The document also discusses biodegradable versus non-biodegradable plastics and their environmental effects. It concludes by recommending following the 4R principles of reduce, reuse, recycle, and recover to be more environmentally friendly.

1. Synthetic fiber and plastic
Chapter 3
Notes

2. Types of fiber
1. Natural
2. Synthetic
Natural fiber :- the fiber that is obtained from nature
like animals examples, plants etc. Some examples
are given below .
Wool Cotton Silk

3. Synthetic fiber :-
1. synthetic fiber are man made .
2. Synthetic fiber are made from different chemicals hence each fiber have their
own properties .
3. Synthetic fiber are more in length and are long in lasting .
4. Synthetic fiber don’t absorb moisture and catches fire easily

4. Polymers and monomers
Polymers are a class of
synthetic substances
composed of multiples
of simpler units called
monomers.

5. Plasti
c
Plastic can be divided into two main categories :-
1. Thermoplastics
2. Thermosetting plastic
Thermoplastic :- plastic that can be easily bent or deform on heating is called
thermoplastic
Thermoplastic are used in making toys, container , combs etc.

6. Thermosetting plastic
1. The plastic that do not bend or softened on heating .
2. Thermosetting plastics are used in making hardboard ,electric switch handle of
kitchen utensils , floor tiles etc.

7. Characteristic of
plastic
Poor conductor :- plastic is a poor conductor of heat and electricity. this make it
suitable to make covering of electrical appliances, Handel of utensils etc. .
Plastic non reactive : - plastic does not react with water and air and many of the
chemicals hence it does not rusted like iron . That’s why it is suitable for making
the container ,water tank
Plastic are strong and durable :- plastic are lightweight , durable , cheap and
very strong . These qualities of plastic made it the need of today whether it is
plaything bags or pencils box , water bottle or umbrellas

8. Biodegradable and non
biodegradable plastic
Substance that get decomposed through natural processes that is action of
bacteria etc ;are called biodegradable substances .
EXAMPLE :- vegetable peels paper , fruits, cotton etc.
Substance that either do not decomposed or take many year to get decomposed
Through the natural process are called non biodegradable substance .
EXAMPLE ;Tin ,aluminum , plastics etc.

9. Environmental Effects on Plastic
1. Plastic takes several years to decompose, it is not environmental friendly.
It causes pollution.
2. The burning process in the synthetic material is quite slow and it does not
get completely burnt easily.
3. It releases lots of poisonous fumes into the atmosphere causing air
pollution in the process.
Implement the 4 R principle in everyday life. Following are the 4Rs:
Reduce
Reuse
Recycle
Recover
These habits are environment-friendly.