18.5 Plastic: here To Stay?

Question 1

What is the advantage of plastics in the Industry?

Answer 1

They are unreactive

Question 2

Why is the unreactivity of plastics a problem?

Answer 2

They will not break down or rot away in the soil. The are non-biodegradable.

The cannot be disposed of easily so the are harmful to the soil and the environment

Question 3

What does non-biodegradable mean?

Answer 3

Will not rot or break down in soil

Question 4

Polythene is the most used plastic in the world. Why is POLYTHENE the biggest problem for environment etc?

Answer 4

1. Polythene ends up in landfill site.
   In the form of plastic bags. They lie around and cause problems.
2. They choke birds, fish and other animals that try to eat them. If they don’t choke them , they will fill up the animals stomachs so they can’t eat proper food and will therefore starve. (Animals can digest plastics)
3. The clog up sewers and cause flooding
4. They collect in rivers and get in the way fish.
5. They blow into trees and onto beaches, so spoils the look of them and reduce the amount of tourists.

Question 5

How do you recycling plastics and reuse them again.

Answer 5

1. Some are melted down and made into new plastic bags and soles for shoes.
2. Some are melted and their long chains are cracked to make small molecules that can be polymerized into new plastics
3. Some are burned and the heat is used to produce electricity
4. Only a small % of plastics can be recycled since you need to separate them before recycling which can be very hard, and burning can produce poisonous gas.

Question 6

What are the 2 ways plastics can be degraded?

Answer 6

Biodegradable - it contains additives such as a starch that bacteria can feed on.

Photodegradable - contains additives that break down in sunlight.

In both cases the polythene breaks down into tiny flakes.

You can any certain amount of additives according to the time you want it to break down ex a plastic bag

Question 7

What is a bio-polymer?

Answer 7

Grown inside plants / made by bacteria in tanks

Some bacteria can feed on sugar from crops (maize) to produce polyester.

Some plants have been developed to make plastic in their cells, then the plastic is extracted by a SOLVENT. Then the solvent is evaporated.

This method can be used when oil (petroleum) runs out.

Their advantage is that they are a renewable resource and are biodegradable.