Polymers

Question 1

Describe polymers

Answer 1

Large molecules made by joining monomers together

Question 2

Describe plastics

Answer 2

Polymer that can be moulded when hot and retains its’ shape when cooled

Question 3

Describe monomers

Answer 3

Molecules that link together to form a polymer

Question 4

Describe addition polymerisation

Answer 4

The process in which monomers with at least one double bond react together to form a polymer by addition reactions

Question 5

Describe condensation polymerisation

Answer 5

Polymerisation in which two monomers combine and a smaller molecule is eliminated

Question 6

Describe polymerisation

Answer 6

The formation of a giant molecules by repeated monomers that are joined by covalent bonds

Question 7

Describe polyethene

Answer 7

A polymer consisting of monomers of ethene

Question 8

Describe rubber

Answer 8

A polymer formed from natural materials

Question 9

Describe thermoplastic

Answer 9

Describes polymers that soften on heating

Question 10

Describe thermosetting

Answer 10

Describes polymers that do not soften on heating and char if heated strongly

Question 11

Describe thermosoftening

Answer 11

Describe polymers that soften on heating to change their shape

Question 12

Describe copolymer

Answer 12

A polymer formed when two different monomers are polymerised

Question 13

Describe cross-linking

Answer 13

The bonding between two polymers

Question 14

Describe elastomer

Answer 14

A polymer that can be stretched and return to its original shape

Question 15

State a more common name for isoprene

Answer 15

Rubber

Question 16

Describe isotactic

Answer 16

A polymer in which the methyl groups are all on the same side of the carbon chain

Question 17

Describe linear polymers

Answer 17

Polymers that do not have a side chains

Question 18

Describe atactic

Answer 18

A polymer in which the methyl groups take random positions in front of and behind the carbon chain

Question 19

Compare and contrast the structure of linear and cross-linked polymers

Answer 19

Linear polymers - straight chain structures

Cross-linked polymers - network structures

Question 20

State the 4 things polymers can be

Answer 20

• non-polar
• polar
• composed of copolymers
• conductive

Question 21

State what the properties of polymers is determined by

Answer 21

• monomers
• additives
• chain length
• branching

Question 22

State the 2 forms of synthetic polymers

Answer 22

1. thermosoftened

2. thermoplastic

Question 23

State whether or not linear polymers melt at high temperatures

Answer 23

No.

Question 24

State whether or not cross-linked polymers melt at high temperatures

Answer 24

No

Question 25

State what occurs to cross-linked polymers when exposed to high temperatures

Answer 25

Tend to become a soft material that eventually burns

Question 26

State what LDPE represents

Answer 26

Low-density polyethene

Question 27

State what HDPE represents

Answer 27

High-density polyethene

Question 28

State the 2 forms in which polyethene is produced

Answer 28

1. LDPE | 2. HDPE

Question 29

State what forces interact with polymer chains if they pack closely together

Answer 29

Weak dispersion forces

Question 30

State whether or not linear polymers are unbrached

Answer 30

Yes. Unbranched

Question 31

State what can increase the strength of polymers

Answer 31

Addition of crystalline areas

Question 32

State what can increase the flexibility of polymers

Answer 32

Addition of plasticisers

Question 33

State what increases in proportion to an increase with crystallinity

Answer 33

Hardness, tensile strength and opacity

Question 34

State what increases with the length of polymer chains

Answer 34

Strength, melting and boiling temperature increases

Question 35

State what long chains are less likely to do when compared to smaller chains

Answer 35

Slide over one another

Question 36

Describe plasticisers

Answer 36

Small molecules added to the components to increase flexibility

Question 37

Provide 1 example of an addition polymer

Answer 37

1. rubber

Question 38

Provide 3 advantages of polymer materials

Answer 38

- moulded into any shape - don't corrode - cheaper raw materials - low density - good insulators - water resistant - chemically inert - unbreakable - relatively cheap to produce

Question 39

Provide 3 disadvantages of polymer materials

Answer 39

- long time to decompose - take up space in landfill - cause pollution in oceans - produce toxic gases on combustion - cause health problems

Question 40

Provide 3 examples of natural polymers

Answer 40

1. wool 2. cotton 3. hair

Question 41

State the 2 ways polymers are made

Answer 41

1. addition polymers | 2. condensation polymers

Question 42

Describe the characteristics of LDPE polymers

Answer 42

Soft, flexible and translucent material with a waxy surface

Question 43

Describe what structure is consistent with the characteristics of LDPE polymers

Answer 43

Large number of long, side branches held by weak dispersion forces

Question 44

Describe the characteristics of HDPE polymers

Answer 44

Less flexible than LDPE, strong and opaque

Question 45

Describe what structure is consistent with the characteristics of HDPE polymers

Answer 45

Few short side branches which are held close by dispersion forces

Question 46

State the 2 polymers which may be produced by the unique arrangements of side branches

Answer 46

1. isotactic | 2. atactic

Question 47

Outline the density of isotactic polymers

Answer 47

High density substance

Question 48

Outline the density of atactic polymers

Answer 48

Low density substance

Question 49

State what the effect of additives is on polymers

Answer 49

Contribute to the appearance and stability of the polymer

Question 50

State what occurs to plastics that can be recycled

Answer 50

Sorted according to standard recycling codes

Question 51

State how plastics are recycled

Answer 51

Shredded, washed and melted to produce chips that can be remoulded