breathable polymers

Question 1

describe the features of nylon (4)

Answer 1

nylon is tough, lightweight, keeps water out and does not let water vapour through.

Question 2

what are the features of gore-Tex?

Answer 2

Gore-Tex has all the properties of nylon but is also breathable.

Question 3

what is GORE-TEX made of?

Answer 3

it is made from a PTFE

Question 4

describe what the holes do in PTFE

Answer 4

The holes in PTFE are too small for water to pass through but are big enough for water vapour to pass through.

Question 5

what is good about the membrane from gore-Tex?

Answer 5

Water vapour from sweat can pass through the membrane but rainwater cannot.

Question 6

what new types of polymers are scientists designing?

Answer 6

• polymers that dissolve

- biodegradable polymers

Question 7

name 3 environmental or economic issues with the use of existing polymers?

Answer 7

• disposal means land fill sites get get filled quicker
• disposal by burning waste plastics release toxic gases
• landfill means wasting land that could be used for valuable purposes

Question 8

what are atoms in a polymer held together by?

Answer 8

strong covalent bonds

Question 9

plastics that have weak intermolecular forces between polymer molecules have what type of melting points?

Answer 9

low melting points

Question 10

what does a low melting point of a polymer mean? and why?

Answer 10

it can be stretched easily as the polymer molecules can slide over one another

Question 11

what type of melting points do strong polymer molecules have?

Answer 11

high

Question 12

and what does this mean?

Answer 12

it can be stretched easily

Question 13

how would you explain a polymer with strong covalent bonds?

Answer 13

rigid

Question 14

what is another word for strong forces between polymer molecules?

Answer 14

covalent bonds or cross-linking bridges

Question 15

name 3 types of polymers?

Answer 15

PVC, polyester and nylon

Question 16

what is nylon used for and why?

Answer 16

clothing as it can make flexible fibres

Question 17

what has the discovery of GORE-TEX helped?

Answer 17

outdoor people to cope with wetness and sweat.

Question 18

what does non-biodegradable mean?

Answer 18

that they do not decay and are not decomposed by bacteria

Question 19

name 3 ways polymers can be disposed of

Answer 19

• in landfill sites
• by burning
• by recycling

Question 20

name 2 problems with disposing of polymers

Answer 20

• difficult to dispose of

- last a long time in land fill sites