Polymers short notes
Polymers short notes and Best notes of polymer class 12 for CBSE exams:- Click on the Download Button
Polymers: They are macro-sized, high molecular mass compounds, formed by the combination of a large number of simple molecules or repeating units.
Click on Below Link for Alcohols, Phenols and Ethers Notes
Monomers: These simple molecules or repeating units which combine to give polymers are called monomers.
The process of joining together of a large number of the monomers is termed as polymerization.
A polymer formed from one type of monomers is called a homopolymer, e.g., polyethylene, PVC, polyacrylonitrile, etc.
A polymer formed from two or more different monomers is called copolymer e.g., Nylon-6,6, polyester, bakelite, etc.
The number of times a monomer unit is repeated in a polymer is called its degree of polymerization.
Classification of Polymers:
Natural polymers: These are substances of natural origin and are mainly found in plants and animals, e.g., starch, cellulose, proteins, etc.
Synthetic polymers: These polymers are prepared in the laboratories, they are also called man-made polymers, e.g., te_on, terylene, synthetic rubber, etc.
Some Important Chemistry Topics
- What is Sugar? Sugar Structure and Formula?
- What is glycerol made of? Is glycerol a sugar?
- What is Chloroform Structure and Formula?
- IUPAC Name: How to find the IUPAC name of compounds.
- What is the use of methanol? Preparation and Properties
- How to make ethyl ether? Properties and Uses
- What is ethyl ether used for? Preparation and Properties
- What are the uses of ammonia gas? Preparation
- What is the formula for stannous chloride?
- What are the physical properties of phosphine?
- What does nitrous acid mean? Preparation and Properties
- What is sodium thiosulfate? Preparation and Properties
- What are the types of amines? Preparation and Properties
- How do you find the Valency of an element?
- Atomic Theory: What is the modern atomic theory?
- What is vitamin and its function? Vitamins in Chemistry
- How are alkanes named? What is alkane formula?
Semi-synthetic polymers: They have mostly derived from naturally occurring polymers by chemical modi_cations, e.g., vulcanized rubber, cellulose nitrate, etc.
Linear polymers: In these polymers monomers are linked together to form linear chains, e.g., polyethylene, polyester, nylon, etc.
Branched-chain polymers: In these polymers the monomers are joined to form long chains or branches of different lengths, e.g., glycogen, starch, etc.
Cross-linked polymers: In these polymers, the monomer units are cross-linked together to form a three-dimensional network polymer, e.g., bakelite, melamine, etc.
Elastomers: These are the polymers having very weak intermolecular forces between the polymer chains. The weak forces permit the polymer to be stretched. Elastomers, thus, possess elastic character, e.g., vulcanized rubber.
Fibers: These are the polymers which have strong intermolecular forces between the chains. These are either hydrogen bonds or dipole-dipole interactions, e.g., Nylon-6,6.
- Lithium Element || How Lithium Ion Batteries Work || Use of Lithium
- What Helium is Used for || Helium Isotopes || How is Helium Made
- Uranium Uses || What is Uranium Used for || How is Uranium Formed
- Platinum alloys || What Platinum is Used for || Platinum Chemical Properties
- Ether Uses || Why Ether is Insoluble in Water || How Ether is Formed
- Magnesium Benefits || Why Magnesium is so Good for You and Properties
Thermoplastics: These are the polymers in which the intermolecular forces of attraction are intermediate between those of elastomers and fibers. These polymers do not have any cross-links between the chains, they can be easily mouled on heating, i.e., thermoplastics so_en on heating and become hard on cooling, e.g., polythene, polystyrene, PVC, etc.
Thermosetting polymers: They have extensive cross-links formed between polymer chains on heating. They undergo a permanent change on heating, e.g., bakelite, melamine, etc.
Addition polymerization: A polymer formed by direct addition of repeated monomers without the elimination of by-product molecules is called addition polymer and the phenomenon is known as addition polymerization, e.g., polythene.
Condensation polymerization: A polymer formed by the condensation of two or more than two monomers with the elimination of simple molecules like water, ammonia, alcohol, etc. is called condensation polymer and The phenomenon is known as condensation polymerization, e.g., Terylene.