What Are Plastics ?

Question 0

What raw materials are used to make plastics and what type of polymer do they make?

Answer 0

Animal and vegetable by products - semi synthetic polymers

Coal , oil and gas - synthetic polymer

Question 1

What are plastics made from?

Answer 1

Made from long chains of molecules - carbon and hydrogen atoms - known as hydrocarbons

Can be from natural sources

Question 2

Give two examples of animal and vegetable by -products and their uses

Answer 2

Cellulose - natural material from plant fibres
Use - mixed with acetic acid - makes cellulose acetate - OHP slides

Casein - by products of milk creat polymer - makes buttons

Question 3

How are synthetic plastics such as coal, oil and gas obtained ?

Answer 3

‘Thermal cracking ‘

Question 4

What are synthetic plastics made from? How often are they used?

Answer 4

Carbon based - account for a majority of plastics

Question 5

What are the three types of plastic?

Answer 5

Thermoplastics
Thermosets - (thermosetting plastics)
Elastomers

Question 6

Properties of a Thermoplastic?

Answer 6

Can be repeated reheated and remoulded

Question 7

Properties of a Thermoset ( thermosetting plastic )?

Answer 7

Undergo a chemical change - become permanently rigid - cannot be reheated and reshaped

Question 8

Properties of an Elastomer?

Answer 8

Good elasticity - distorted under pressure - return to original shape - when pressure removed

Question 9

General properties of plastics (6)

Answer 9

• Good electrical and thermal insulators
• Good strength to weight ratio
• Good atmospheric and chemical corrosion resistance
• Low melting temps - ( thermoplastics only)
• Lightweight
• Self coloured, opaque, translucent or transparent - depends on type of polymer and processing used