Question

Explain natural and synthetic polymers (rubber) and mention their monomers.

Answer 1

Hint: Polymers are a wide range of compounds which are synthetic (man-made) as well as naturally produced. For a single type of polymer which is obtained naturally can be synthetically in laboratories as well as industries on large scale.

Complete step by step answer:
Polymers are the long chain compounds which have the same recurring unit throughout which is called a monomer. Rubber is obtained from trees naturally and was among the first polymers recognized and used. If we consider the micro-structure then the recurring unit i.e. monomer present in it is isoprene. Natural rubber has a single monomer isoprene but it can have many different stereoisomers also
  

this is the main monomer unit isoprene

This cis stereoisomer is almost present in ${\text{100% }}$ amount in natural rubber.
  

This is also a monomer but very less likely present with this trans stereo. The natural rubber has more molecular mass than the synthetic rubber.
Synthetic rubber is an artificially made elastomer. It is made from petroleum products mainly. Synthetic rubbers are more widely used because they are reliable due to different ranges of physical and chemical properties. Synthetic rubbers are also made from isoprene units but the most widely used monomers of synthetic rubber are styrene and buta-diene.
 

Styrene Buta-diene

Additional information:
The first synthetic rubber was made in 1910 by Russian scientists which have butadiene as its monomer. This was synthesized on a large scale due to high demands during world war but again it was replaced by natural rubber because of less reliability. After regular discoveries synthetic rubber is more widely used now.

Note: Synthetic rubber is widely used for its reliability. They are better than natural in two ways because of high thermal stability and resistance to various oils and compounds. They are resistant toward oxidizing agents also because of which the life of tires was greatly reducing.