3.3.12 Polymers

Question 1

2 types of molecule that react to form
Polyamides
Polyester

Answer 1

Dicarboxylic acids + diamines
Dicarboxylic acids + diols

Question 2

Draw repeating units of
Nylon 6,6
Kevlar
Terylene

Answer 2

-

Question 3

Intermolecular forces between condensation polymers

Answer 3

Hydrogen bonds between polymer chains

Question 4

Why can polyesters and polyamides be hydrolysed but not polyalkenes

Answer 4

Water hydrolyses the amide link forming diamines and dicarboxylic acids
Water hydrolsyes the ester link forming diol and dicarboxylic acids
Polar bonds can be attacked by nucleophiles
Polyalkenes have strong non-polar bonds

Question 5

Burying waste advantages and disadvantages

Answer 5

A- Cheap and Easy
D- Requires lots of land, methane released as waste decomposes, toxins released which contaminate water supplies, not enough land

Question 6

Burning waste plastic advantages and disadvantages

Answer 6

A- Heat from burning used to generate electricity, can be controlled to reduce toxic gases - HCl reacts with base and be neutralised
D- toxic gases such as CO2 produced

Question 7

Recycling advantages and disadvantages

Answer 7

A- Reduces landfill, saves raw materials, cheaper than making plastic from scratch, less CO2 produced than burning
D- Technically difficult, expensive to collect, sort and process plastic, often can’t make plastic you started with, plastic can be contaminated during recycling process

Question 8

Explain why polyesters are biodegradable but polyalkenes are not biodegradable

Answer 8

polyesters: C=O/C−O OR polar bonds
polyalkenes: C−C OR non-polar bonds
polyesters susceptible to nucleophilic attack / can be hydrolysed

Question 9

Which molecules react to form condensation polymers

Answer 9

Dicarboxylic acid + diols
Dicarboxylic acid + diamines
Amino acids