Question

What are biodegradable polymers? Give a chemical equation for the preparation of any one biodegradable polymer.

Answer 1

Hint: A product formed by the repeating addition of simple molecules called monomers with byproducts such as water, ammonia etc.
- It finds application in different fields due to its nature friendly characteristics.

Complete step by step solution:
By the name itself we can guess that the substance is a polymer which has the biodegradable property, i.e. it easily gets degraded by the microbial actions like attack of bacteria. And such polymers don't retain in the earth for a longer period causing damage to the soil.
-Polymer is a substance which occurs naturally or synthesized by the addition, condensation or ring opening reactions with suitable catalysts.
-Biodegradable polymers easily gets converted into simples molecules like \[{{H}_{2}}O,N{{H}_{3,}},C{{O}_{2,}}{{N}_{2}}\] etc. by the decomposition reaction of the bacteria. As the final products are very much eco friendly as they are not hazardous for the earth, the biodegradable materials are finding huge application in many fields.
-In the monomer may contain functional groups such as ester, amide, amino group, carboxylic acid group which all undergo breakage and link with another molecule to give the polymers.
-Best examples for the biodegradable polymers are poly glycolic acid (PGA), Nylon-2-nylon -6, polycaprolactone, poly hydroxy butyrate.
Preparation of nylon-2-nylon 6, The monomers are glycine and amino caproic acid
$nN{{H}_{2}}-C{{H}_{2}}-COOH+nN{{H}_{2}}-{{\left( C{{H}_{2}} \right)}_{5}}-COOH\to \left[ -CO-C{{H}_{2}}-NH-CO-{{(C{{H}_{2}})}_{5}}-NH- \right]$

The polymer is called nylon-2 –nylon -6 since there are 2 Carbon atoms in glycine and 6 carbon atoms in amino caproic acid.

Note: There are various classifications in biodegradable polymers. Mainly there are three types of polymers-natural polymers, synthetic polymers and modified natural polymers. And again it is subdivided into many classes. We get confused between the monomers used since all sound the same. With the change in one monomer the whole polymer will be modified.