What is Polymers

What is Polymers?

Polymers are macro-sized molecules of comparatively high molecular masses which find in depth use in our daily life. They are obtained by joining together a large number of tiny molecules. Structurally they are characterized by several continuation molecular units that form linear chains or a cross-linked network. 

The method of formation of polymers from their beginning materials is called polymerization and the tiny molecules that mix with each other are called as monomers. Example is Polythene is the polymer of ethylene.

What is Polymers

-:Classification of Polymers:-

Classifications based on Source of Availability:

1) Naturally Occurring Polymers –

Example - Proteins, Nucleic acids, Cellulose, Rubber.

2) Semi-Synthetic Polymers –

Cellulose on acetylation with acidic anhydride in nearness of Sulphuric corrosive structures cellulose diacetate utilized in making strings and materials like movies, glasses and so on. Vulcanized rubber is used in making tyres. Gun-cotton (Cellulose nitrate) is used in making explosive.

3) Synthetic Polymers –

Example – fibres, plastics, synthetic rubber.

Classification based on Mode of Polymerisation:

1) Homopolymers and Co-polymers –

Polymer having only one chemical species are known as homopolymers , like – polythene polymer having two or more than two chemical species are known as Co-polymers. Example is Styrene-butadiene rubber.

2) Addition and Condensation Polymers –

Polymer formed by reactions between monomer molecules processing multiple bonds. Like Styrene butadiene rubber.

Polymers are formed by Condensations between monomeric units with the elimination of small molecules such as water, ammonia, alcohol, etc. example is Nylon-66.

Classification based on Molecular Forces:

1) Elastomers –

The polymer chains are held together by the weakest intermolecular forces in such a way that permit the polymer to be stretched. Example is Vulcanized rubber.

2) Fibres –

The polymers which possess high tensile strength and high modulus that attributed to the strong intermolecular forces and impart crystalline nature are called fibre. Example is Polyamides.

3) Thermoplastics  -

The polymers that possess intermediate intermolecular forces of attraction between elastomers and fibres and having no cross-linking but easily moduled by heating are called thermo-plastics. Example is Polystyrene, Polythene.

4) Thermosetting Polymers –

The polymers that are made from relatively low molecular mass semi-fluid polymers and forms insoluble and infusible hard mass on heating due to extensive cross-linking between different polymer chains called Thermo-setting polymer. Example is Bakelite.