Polymers

?
  • Created by: Hindleyc
  • Created on: 24-03-19 12:22
What are the 2 types of polymerisation?
Addition and condensation
1 of 82
How does an addition polymer form?
An addition polymer forms when unsaturated monomers react to form a polymer
2 of 82
What do the monomers contain?
C=C double bonds
3 of 82
What are poly(alkenes)? why?
Chemically inert due to the strong C-C and C-H bonds and non-polar nature of the bonds and therefore are non-biodegradable
4 of 82
When do chains form?
When the same basic units is repeated over and over
5 of 82
How to draw repeat unit?
First draw out the monomer with groups of atoms arranged around the double bonds then trail bonds and make the middle bond single and brackets and n
6 of 82
How are condensation polymers formed?
By reactions between: dicarboxylic acids + diol= poly(esters) + water, Dicarboxylic acid + diamine=poly(amide) + water, amino acids= polypeptide
7 of 82
What are the 2 most common types of condensation polymers and what do they involve the formation of?
polyesters and polyamides which involve the formation of an ester linkage (polyesters) or amide linkage(polyamides)
8 of 82
What happens in condensation polymerisation?
There are 2 different monomers that add together and a small molecule is usually given off as a side product eg H2O, HCl
9 of 82
What would the monomers usually have?
Same functional group on both ends of the molecule eg diamine, dicarboxylic acid, diol, diacyl chloride
10 of 82
Carboxylic acid+Alcohol
ester + water
11 of 82
Carboxylic acid + amine
Amide + water
12 of 82
Acyl chloride + alcohol
ester + HCl
13 of 82
Acyl chloride + amine
Amide + HCl
14 of 82
If we have the same FG on each end of the molecule what can we make
Polymers
15 of 82
Dicarboxylic acid +diol=
Poly(esters) + water
16 of 82
Dicarboxylic acid+ diamine=
Poly(amide) + water
17 of 82
Diacyl dichloride + diol=
Polyester + HCl
18 of 82
Diacyl dichloride + diamine
Poly(amide) + water
19 of 82
Amino acids
Polypeptide (same linkage as polyamides made from just AA monomer
20 of 82
What would using the carboxylic acid to make the ester or amide need ?
An acid catalyst and would only give an equilibrium mixture
21 of 82
What does The more reactive acyl chloride do?
goes to completion and doesn't need a cataylst but does produce hazardous HCl fumes
22 of 82
What is Terylene?
A common polyester
23 of 82
What is there between repeating units
Ester linkage
24 of 82
EQN
n Benzene-1,4-dicarboxylic acid + n Ethane-1,2-diol =n terylene + 2n-1 H2O
25 of 82
Why -1
Because at each end of the chain the H and OH are still present
26 of 82
What is Terylene fabric used in
Clothing , tire cords (as fibre for making clothes)
27 of 82
How to draw polymer
Remove OH from COOH and H from OH
28 of 82
What is Nylon 6,6
A common polyamide
29 of 82
What does it have between repeating units
Peptide linkage
30 of 82
What is it used in
Parachutes, waterproof in nature, swimwear, tires, ropes
31 of 82
What is used in lab?
Hexane-1,6-diacyl chloride as ROR faster, HCl eliminated
32 of 82
EQN
N Hexanedioic acid + n hexane-1,6-diamine = n Nylon 6,6 +2n-1 H2O
33 of 82
What does the 6,6 stand for?
6 carbons in each of the monomers
34 of 82
What do different length carbon chains produce
Different polyamides
35 of 82
What is Kevlar?
a common polyamide
36 of 82
What is it used in?
Body armour (bullet proof vests, stab vests, helmets, oven gloves
37 of 82
What is it? why?
Strong -rigid chains and close packing of flat aromatic rings
38 of 82
EQN
n Benzene-1,4-dicarboxylic acid + n 1,4-diaminobenzene = n kevlar +2n-1 H2O
39 of 82
What happens to NH2 at end
NH
40 of 82
Type of polymer
poly amide or poly ester etc
41 of 82
Type of polymerisation
addition/ condensation
42 of 82
What is also possible?
For poly amides and poly esters to form one monomer if that monomer contains both the functional groups needed to react
43 of 82
What is it possible for some of these compounds to form
various cyclic esters under diff conditions from forming the polymer eg ring diester
44 of 82
What can polyesters and polyamides be broken down by?
Hydrolysis
45 of 82
What are they therefore
Biodegradable
46 of 82
How can reactivity be explained?
By the presence of polar bonds which can attract attacking species such as nucleophiles and acids
47 of 82
What is rate of hydrolysis in standard conditions
V slow
48 of 82
What can polyesters and polyamides be hydrolysed by?
acid and alkali- biodegradable
49 of 82
What will the hydrolysis result in
The original monomer forming although the carboxylic acid or amine group will be in salt form depending on whether the conditions are alkali or acidic
50 of 82
Why can condensation be broken down?
bc they have polar bonds
51 of 82
Polymer n +HCl
di carboxylic acid + diamine with NH3+
52 of 82
Polymer n + NaOH
Dicarboylic acid with COO- and amine alcohol
53 of 82
What IM forces do polyesters have?
Permanent dipole forces between the C=O groups in the different chains in addition to the V.D.W forces between the chains
54 of 82
Why do Polyesters not show H bonding
All OH bonds removed during polymerisation
55 of 82
What do polyamides and proteins have
hydrogen bonding between the oxygen in the C=O groups and H in the N-H group in the different chains in addition to the Van Der Waals forces
56 of 82
What will polyamides therefore have?
Higher melting points than polyesters
57 of 82
Difference between condensation and addition polymerisation
Condensation makes polymer and eliminates a small molecule, Addition breaks C=C to form only one product-just the polymer
58 of 82
Ways to dispose of polymers
Landfill, incineration, recycling,
59 of 82
What is landfill
Most common method of disposal of waste in the UK
60 of 82
What happens to polyalkenes
Inert and non-biodegradable
61 of 82
What are many sites now doing
reaching capacity
62 of 82
What will European regulations mean
Councils are charged more for using landfill
63 of 82
What are most polymers (polyalkenes)
non-biodegradable and take many years to break down
64 of 82
What could be used?
More biodegradable plastics eg polyamides and cellulose and starch based polymers to improve rate of decomposition
65 of 82
What is Incineration
Rubbish is burnt and energy produced is used to generate electricity
66 of 82
What can be released on Incineration
Some toxins
67 of 82
How can modern incinerators now burn
More efficiently and most toxins and pollutants can be removed
68 of 82
What will still be emitted though
Greenhouse gases
69 of 82
What is greatly reduced
Volume of rubbish
70 of 82
How does recycling work
Collected, sorted, melted, reformed
71 of 82
What does it save
Raw materials- nearly all polymers are formed from compounds sourced/ produced from crude oil
72 of 82
What does it save
Precious resources
73 of 82
What do polymers need
Collecting/ sorting- expensive process in terms of energy and manpower
74 of 82
What can polymers only be recylced into
The same type- so careful separation needs to be done
75 of 82
What can thermoplastic polymers do
Be melted down and reshaped
76 of 82
What does recycling do
Saves expense of crude oil and preserves and non-renewable resource
77 of 82
What else
Reduces landfill
78 of 82
Disadvantages
Energy and manpower needed for collecting, sorting and melting the polymers making it expensive
79 of 82
What else
Can only be done a limited number of times
80 of 82
When asked for polymer
Square brackets, n, trailing bonds
81 of 82
Repeat unit
Molecule, trailing bonds, no brackets or n
82 of 82

Other cards in this set

Card 2

Front

How does an addition polymer form?

Back

An addition polymer forms when unsaturated monomers react to form a polymer

Card 3

Front

What do the monomers contain?

Back

Preview of the front of card 3

Card 4

Front

What are poly(alkenes)? why?

Back

Preview of the front of card 4

Card 5

Front

When do chains form?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Polymers resources »