Polymers Flashcards
(14 cards)
Define condensation polymerisation
Involves 2 diff. monomers, each with at least 2 diff. functional group. Functional group react forming a link
Outline how polyamides are formed
Dicarboxylic acid + diamines
Carboxyl group of dicarboxylic acid reacts w/ amino group of diamines forming amide link
Give an example of a polyamide?
Nylon + Kevlar
Nylon
What is it used for?
- 1,6- diaminohexane + hexanedioic acid
- Clothing, carpet, rope
Kevlar
What is it used for?
1, 4-diaminobenzene + benzene-1,4-dicarboxylic acid
Bulletproof vest, car tyres
Outline how polyesters are formed
Give an example
Dicarboxylic acid + diols
Carboxyl on dicarboxylic acid reacts w/ hydroxyl on diol to form ester link
Give an example of a polyester + what its used for
Terylene → benzene-1,4-dicarboxylic acid + ethane-1,2-diol
Plastic bottles, clothes
Which is stronger, condensation polymers or addition polymers?
- Condensation polymers
- Made up of chains containing polar bonds so contain VDW, DP + H bonds
Advantage + disadvantage of polyalkenes
- Polyalkenes: polyethene + polystyrene (addition polymers)
- Non-polar C bonds so unreactive + inert
- Non-biodegradable
Advantage + disadvantage of condensation polymers
- Have polar bonds so prone to attack by nucleophiles, can be broken down by hydrolysis - biodegradeable
- Slow process
Burying plastic
- Used when:
- difficult to seperate from other waste
- Too difficult to recycle
- Cheap + easy
- Requires land
- As waste decomposes it releases methane - contaminates water suplies
Burning plastic
- Heat used to generate electricity
- Releases toxic gas
- waste gas passed through scrubbers which neutralise gas
Recycling plastics
- After plastics are sorted they can be:
- melted + remoulded
- Cracked into monomers -used to make new plastics or other chemicals
Give 2 advantages + disadvantages of recycling plastics
- Reduces waste going into landfill
- Produces less CO2 emission than burning plastic
- Plastic can be contaminated
- More expensive
