Question

Answer the following questions:
1. Define non-biodegradable polymers.
2. Write the preparation of terylene.

Answer 1

Hint: The answer is based on the concept of polymers where the name non – biodegradable itself tells the definition and the monomers used for the preparation of terylene are the one belonging to the family glycol and terephthalate.

Complete answer:
In the classes of physical chemistry, we have studied the basic concept that deals with the polymers and the preparation of some common polymers and their properties along with uses.
Now, let us see the definition of the terms and also the preparation of terylene.
1. Non – biodegradable polymer, the name itself indicates that it cannot be degraded in the biological process.
- In a simpler way, Non – biodegradable polymers can be defined as they are those polymers which are resistant to the environmental degradation and hence they end up in the form of waste.
Examples for these non – biodegradable polymers are polystyrene, polyethylene etc.
These non – biodegradable polymers are used for the energy recovery which involves the process called pyrolysis that is the controlled thermal decomposition in the absence of oxygen.

2. The preparation of the polymer terylene is carried out using the two monomers namely ethylene glycol (1,2 – ethanediol) and dimethyl terephthalate and the catalyst that is used is the mixture of zinc acetate and antimony trioxide.
The process of polymerisation of these two polymers is the condensation polymerisation.
- In this process, monomers are heated to 503 K where the formation of another monomer called dihydroxy diethyl terephthalate is formed and this on further heating yields polymerized product terylene.
The process is as shown below,

Note:
Note that terylene is also called as Dacron and it is a polymer, polyethylene terephthalate which is basically used for the preparation of threads and cloth and terylene is the synthetic polyester fibre.