6.2.3 Polyesters And Polyamides Flashcards
1
Q
What are addition polymers formed from?
A
- alkenes undergoing addition reactions
- joined in the presence of high pressure and a catalyst
2
Q
How are addition polymers formed?
A
- the π bond breaks and the molecules join together to form a long chain polymer
- there are no other products besides the polymer
3
Q
What are condensation polymers?
A
- formed from condensation reactions between monomers
- a small molecule is produced as well as the polymer
4
Q
What are polyesters?
A
- formed when a dicarboxylic acid reacts with diols
- polymer contains an ester link
- O-C=O
5
Q
What are polyamides?
A
- have an amide link between monomers
- O=C-N-H
6
Q
How many molecules of water are formed from condensation polymers?
A
- 2n-1
7
Q
Why are polyesters and polyamides biodegradable?
A
- they can be hydrolysed in the presence of acid and catalyst into their constituent alcohol and carboxylic acid
- so they are biodegradable
8
Q
What are the conditions for hydrolysis of condensation polymers?
A
- hot aqueous acid (HCl)
- aqueous base (NaOH)
- both in presence of heat
9
Q
What are polyesters hydrolysed into?
A
Base hydrolysis:
- sodium salt of carboxylic acid
- alcohol
- each ester linkage is hydrolysed into
Acid hydrolysis: (slower r of r)
- dicarboxylic acid
- alcohol
- monomer units produced
10
Q
What are polyamides hydrolysed into?
A
Base hydrolysis:
- sodium salt of carboxylic acid
- diamine with 2 NH2 groups
Acid hydrolysis:
- dicarboxylic acid
- ammonium salt of the diamine (NH3+)
