performance charateristics of polymers

Question 1

Give the 6 stock forms of polymers

Answer 1

Granules, Sheet, Film, Rods and other extruded form, tubes, bars, Foam, Powder

Question 2

Define thermoplastic polymer and give five examples

Answer 2

A material that can be reheated and reshaped repeatedly, allowing it to be recycled after its initial use.

Examples: LDPE, HDPE, PP, HIPS, ABS, PMMA (acrylic), Nylon, uPVC, PVC

Question 3

State three properties/characteristics of LDPE

Answer 3

Lightweight, Low level of rigidity, Good chemical resistance

Question 4

State two uses of LDPE

Answer 4

Detergent bottles, Toys, Carrier bags, General packaging, Food wrap film

Question 5

State three properties/characteristics of HDPE

Answer 5

Tough, Good chemical resistance, Good stiffness

Question 6

State two uses of HDPE

Answer 6

Bottles, Crates, Buckets, Bowls

Question 7

State three properties/characteristics of PP

Answer 7

Lightweight, Food-safe, Good impact resistance, Good chemical resistance, Tough

Question 8

State two uses of PP

Answer 8

Kitchen products, Medical equipment, Rope, Folders

Question 9

State three properties/characteristics of HIPS

Answer 9

Good impact resistance, Good stiffness, Lightweight, Hard, Tough

Question 10

State two uses of HIPS

Answer 10

Yoghurts pots, Refrigerator linings, Single-use drinks cups, Toilet seats

Question 11

State two properties/characteristics of ABS

Answer 11

Tough, Hard

Question 12

State two uses of ABS

Answer 12

Safety helmets, Toys, Computer housing, Rigid luggage

Question 13

State three properties/characteristics of PMMA

Answer 13

Tough, Hard, Good chemical resistance, Food-safe, Durable, Easily machined

Question 14

State two uses of PMMA

Answer 14

Illuminated signs, Car light casings, Baths, Lightning units/covers

Question 15

State three properties/characteristics of Nylon

Answer 15

Tough, Corrosion resistance, Good temperature resistance, Low coefficient of friction

Question 16

State two uses of Nylon

Answer 16

Gears, Textiles, Bearings, Curtains rails

Question 17

State three properties/characteristics of uPVC

Answer 17

Rigid opaque, Tough, Hard, Good weathering resistance, Good chemical resistance

Question 18

State two uses of uPVC

Answer 18

Windows frames, External doors, Water service pipes, Guttering and downpipes for buildings

Question 19

State three properties/characteristics of PVC

Answer 19

Tough, Good weathering resistance, Good chemical resistance, Flexible

Question 20

State two uses of PVC

Answer 20

Hose pipes, Cable insulation, Medical grade tubing

Question 21

Define thermoset polymer and give three examples

Answer 21

A material that, when heated, undergoes a chemical change whereby the molecules form rigid cross-links. They cannot be reheated and reshaped.

Examples: Urea-formaldehyde (UF), Melamine formaldehyde (MF), Polyester resin, Epoxy resin

Question 22

State three properties/characteristics of UF

Answer 22

Hard, Tough, Good electrical insulator, Brittle

Question 23

State two uses of UF

Answer 23

Electrical fittings, Adhesives

Question 24

State three properties/characteristics of MF

Answer 24

Hard, Opaque, Tough, Heat resistant, Food safe, Chemical resistant

Question 25

State two uses of MF

Answer 25

Decorative laminates, Picnic ware, Buttons

Question 26

State three properties/characteristics of polyester resin

Answer 26

Rigid, Heat resistant, Chemical resistant, Brittle

Question 27

State two uses of polyester resin

Answer 27

Castings, Car parts, Chair seats

Question 28

State three properties/characteristics of epoxy resin

Answer 28

Rigid, Hard, Tough, Chemical resistant

Question 29

State two uses of epoxy resin

Answer 29

Adhesives, Surface coatings, Cardiac peacemaker, Aerospace

Question 30

Define elastomer and give three examples

Answer 30

A material that can be deformed under pressure and that returns to its original shape when pressure is released. ## Footnote Examples: Natural rubber, Butadiene rubber (BR), Neoprene, Silicone

Question 31

State three properties/characteristics of natural rubber

Answer 31

High tensile strength, Low elongation, Good hardness, Tough, Electrical insulator, Good cold resistance

Question 32

State two uses of natural rubber

Answer 32

Tyres, Tubes, Hoses, Footwear, Toys

Question 33

State three properties/characteristics of BR

Answer 33

Tough, Excellent wear resistance against friction, Good thermal resistance against friction, Electrical insulator

Question 34

State two uses of BR

Answer 34

Vehicle tyres, Shoe soles, Toys

Question 35

State three properties/characteristics of neoprene

Answer 35

Good thermal resistance, Toughness, Good oil and chemical resistance, Excellent weather resistance, Good abrasion resistance, Electrical insulator

Question 36

State two uses of neoprene

Answer 36

Wet suits, Laptop cases, Industrial wires insulation, Transmission belts

Question 37

State three properties/characteristics of silicone

Answer 37

Poor abrasion resistance, Good thermal resistance, Good weather resistance, Good lubricating qualities, Electrical insulator

Question 38

State two uses of silicone

Answer 38

Flexible ice cube trays, Bakeware, Cooking utensils, Medical uses as lubrication for prosthetics