Hint: Polymers are the substance which has a large size that's why they are also known as macromolecules. The polymers are made up of the long chain of a single repeating unit which can be single as well as different. Some polymers may be found naturally in the environment whereas some can be synthesised by the humans, artificially.
Complete answer: -The formation of the polymer takes place by the process of polymerisation in which the single repeating unit makes a bond with each other and forms a long chain known as a polymer.
-The small repeating unit of the polymer is known as a monomer.
-There are two types of polymer i.e. synthetic and natural polymer.
-Both types of polymers play an important role in the daily life of human beings.
-Natural polymer: Those polymers which can be found naturally in the environment are known as natural polymers. They can not be synthesised artificially by the human being. They can be synthesised by both plants and animals.
-The formation of the natural polymer takes place through the biological process.
-Natural polymers can be easily degraded in nature.
For example, starch, proteins, cellulose, natural rubber, etc.
-Here, starch is a polymer which is formed when about 100 molecules of glucose make the bond with others and the bond formed is also known as a glycosidic bond.
-Moreover, Natural rubber is also a natural polymer which is made by the polymerization of 2 - methylbuta - 1, 3 - diene.
-Synthetic polymer: Those polymers which can be synthesised artificially in the labs are known as synthetic polymers. They can be synthesised artificially by the human being in the laboratory.
-The degradation of synthetic polymers in nature is difficult.
- For example, Polyethylene, synthetic rubber, etc.
-Synthetic rubber is a synthetic polymer which is made by the polymerization of 1 - butadiene.
-Polyethene is also a synthetic polymer which is made by the polymerization of an unsaturated hydrocarbon i.e. ethene.
Note: There are two types of polyethene, based on the density of the polyethene i.e. low-density polyethene which is used in making toys and high-density polyethene (harder than low-density polyethene) which is used in making containers and pipes