polymers

Question 1

stock forms

Answer 1

• powder
• granules
• sheet
• foam
• film
• rods and other extrusions
• bar
• tube

Question 2

synthetic polymers

Answer 2

• made from crude oil
• take hundreds of years to degrade

Question 3

self finishing

Answer 3

• polymer can be pigmented during manufacture to give colour
• requires no additional secondary finishing

Question 4

types of polymer

Answer 4

• thermoplastic
• thermoset
• elastomer

Question 5

thermoplastics

Answer 5

• can be reheated and reshaped repeatedly
• can be recycled after initial use

Question 6

thermoset

Answer 6

• when heated, undergo a chemical change where molecules form rigid cross links
• cannot be reheated and reshaped

Question 7

elastomers

Answer 7

• at room temperature can be deformed under pressure
• upon release of pressure it will return to its original shape

Question 8

LDPE

Answer 8

• thermoplastic
• tough
• good chemical resistance
• low rigidity
• carrier bags
• food wrap film
• squeezy bottles

Question 9

HDPE

Answer 9

• thermoplastic
• tough
• weather proof
• good chemical resistance
• chemical drums
• toys
• buckets
• bowls

Question 10

polypropylene

Answer 10

• thermoplastic
• tough
• good fatigue resistance
• good chemical resistance
• rope
• food containers
• medical equipment

Question 11

HIPS

Answer 11

• thermoplastic
• lightweight
• flexible
• easily vacuum formed
• containers
• yoghurt pots

Question 12

ABS

Answer 12

• thermoplastic
• tough
• durable
• good impact strength
• rigid luggage
• control cases and handsets

Question 13

PMMA (acrylic)

Answer 13

• thermoplastic
• tough
• brittle
• easily scratched
• good chemical resistance
• car lights
• baths

Question 14

nylon

Answer 14

• thermoplastic
• tough
• corrosion resistant
• good temperature resistance
• low coefficient of friction
• cable ties
• boil in the bag food packaging
• gears and bearings

Question 15

uPVC

Answer 15

• thermoplastic
• rigid
• tough
• good chemical resistance
• good weathering resistance
• window frames
• doors
• pipes

Question 16

PVC

Answer 16

• thermoplastic
• flexible
• tough
• easily extruded
• good chemical resistance
• good weathering resistance
• pipes
• hard hats

Question 17

PET

Answer 17

• thermoplastic
• easily blow moulded
• food safe
• bottles
• packaging

Question 18

MF

Answer 18

• thermoset
• food safe
• hard
• tough
• heat and chemical resistant
• kitchenware
• work surfaces

Question 19

UF

Answer 19

• thermoset
• good electrical insulator
• hard
• brittle
• heat resistant
• electrical casings
• electrical handles

Question 20

polyester resin

Answer 20

• thermoset
• strong
• heat resistant
• chemical resistant
• casings
• coatings

Question 21

epoxy resin

Answer 21

• thermoset
• rigid
• clear
• hard
• tough
• chemical resistant
• adhesives
• surface coatings
• encapsulation of electrical components

Question 22

natural rubber

Answer 22

• elastomer
• high tensile strength
• electrical insulator
• low elongation
• tough
• footwear
• tyres

Question 23

butadiene rubber

Answer 23

• elastomer
• tough
• excellent wear resistance against friction
• good thermal resistance against friction
• electrical insulator
• shoe soles
• conveyor belts

Question 24

neoprene

Answer 24

• elastomer
• good thermal resistance
• excellent weather resistance
• good abrasion resistance
• wetsuits
• laptop cases
• door seals

Question 25

silicone

Answer 25

- elastomer - good flexibility at low temperatures - poor abrasion resistance - good thermal resistance and resistance to temperature extremes - good weather resistance - flexible trays - baking moulds - medical tubing for drug delivery systems