6.5 polymers

Question 1

example of a monomer and polymer

Answer 1

propene to make poly(propene)

Question 2

what type of molecule are poly(alkenes)

Answer 2

• saturated
• normally non-polar, so unreactive
• dont biodegrade well

Question 3

2 types of condensation polymers

Answer 3

polyamides and polyesters

Question 4

what is condensation polymerisation

Answer 4

2 different monomers with at least 2 functional groups react together, a link is made and water is eliminated

Question 5

how are polyamides formed

Answer 5

diamines and dicarboxyic acids together

Question 6

how are polyesters formed

Answer 6

diol and dicarboxylic acids together

Question 7

why are dicarboxylic acids/diamines/diols used

Answer 7

they have functional groups on either side which allows chains to be formed

Question 8

reverse of polymerisation

Answer 8

hydroylisis of condensation polymers

Question 9

how to hydroylse a polyester or polyamine

Answer 9

1. break the bond in the middle of the amide/ester link
2. add 2H2O to the monomers

Question 10

how to work out the monomer from the polymer chain

Answer 10

look for
* amide link: HN-CO
* ester link: CO-O

Question 11

how can condensation polymers be formed from one type of monmer

Answer 11

using molecules with a carbox and alcohol/amine group can react with itself

Question 12

why are polymers bad for the environment

Answer 12

alkenes are made from crude oil which is a finite resource and they often end up on landfills

Question 13

how can polymers be recycled/re-used

Answer 13

• recycling sorted into types and then chopped into flakes, washed dried and used to make new products
• PVC recycling hazardous due to Cl content. solvents dissolve PVC and it’s recovered by precipitation and the solvent is reused
• using as a fuel incinerated to produce heat, generating steam to drive a turbine, producing electricity
• feedstock recycling chemical and thermal process that can reclaim monomers, gases, or oil from waste polymers which can be used to produce new polymers. advantage = don’t need to be sorted or washed

Question 14

alternative polymers

Answer 14

biodegradable polymers - can be broken down by microorganisms into water, carbon dioxide and biological compounds
photodegradable polymers - oil based but are treated so light can be used as a trigger to start the degration process

Question 15

what’s released when PVC is burnt + why bad

Answer 15

hydrogen chloride, a corrosive gas