Plastics and moulding

Question 1

What are thermoplastics?

Answer 1

a material that, once produced, can be formed using heat into a variety of different shapes through blow moulding etc. They can be reheated, softened, reshaped and cool many times over why also being easily recyclable.

Question 2

What are thermosetting plastics?

Answer 2

made up of two components ( a resin and catalyst ) and are usually in the form of liquids or paste, but when coming together turn hard. they cannot be reshaped or reheated, so they are not easily recyclable.

Question 3

Name at least 5 different types of thermoplastics.

Answer 3

1. Acrylic - CD cases, baths
2. HDPE (High density polyethylene) - buckets, water tanks, water pipes
3. LDPE (Low density polyethylene) - packaging film, cable insulation
4. PET (Polyethylene terephthalate) - fizzy drink bottles
5. PVC (Polyvinyl chloride) - Floor covering, pipes and guttering
6. PP (Polypropelene) - Carpets, kitchenware, syringes
7. PS (Polysterene) - insulation, packaging
8. ABS - helmets, mobile phones

Question 4

Which plastic is made up of long chains of molecules, with the chains being held together by small cross links?

Answer 4

Thermoplastic

Question 5

Which plastic has molecules that link side to side and end to end?

Answer 5

Thermosetting

Question 6

Name at least 2 different types of thermoplastics.

Answer 6

1. Epoxy resins - Electronics, adhesives, paints
2. Urea formaldehyde - electric fittings
3. polyester resin - garden furniture, glass in boats and cars

Question 7

Name at least 3 different ways of making a product out of plastcis

Answer 7

Injection moulding, extrusion, blow moulding, vacuum forming and rotational moudling

Question 8

Which plastic can be used in injection moulding?

Answer 8

Both

Question 9

What is injection moulding?

Answer 9

Molten plastic being injected under pressure into a mould

Question 10

What is extrusion?

Answer 10

Molten plastic being forced through a die of the desired cross section

Question 11

What is blow moulding?

Answer 11

plastic gets heated up and will soften, which will allow it to extrude into a hollow tube with air pumping in it to set it into a shape of a hollow product

Question 12

What is vacuum forming?

Answer 12

kind of the same as blow moulding, using thermoplastics.

Question 13

Products made by blow moulding and plastics used

Answer 13

HDPE, LDPE, PET, PP, PS AND PVC - Bottles, containers

Question 14

Products made by injection moulding and plastics used

Answer 14

ABS, HDPE, NYLON, PP AND PS - Casing, containers

Question 15

Products made by vacuum forming and plastics used

Answer 15

ACRYLIC, HIPS, PVC - Yoghurt pots, insides of fridges.

Question 16

What is rotational moulding

Answer 16

Powered polymer is loaded into a mould, the mould rotates the sticky melted powder against the wall and the mould is then cooled by air/water