3.12- Polymers Flashcards
How does addition polymerisation work
An addition polymers form when unsaturated monomers react to form a polymer monomers contain C=C bonds
Why are polyalkenes chemically inert
They are chemically inert due to the strong C-C and C-H bonds, and non polar nature of the bonds and therefore are non biodegradable
How does condensation polymerisation work
There are two different monomers that add together and a small molecule is usually given off as a side product, they usually have the same functional group on both ends of the molecule
Give 3 forms of polymers made from condensation
Polyesters, polyamide and polypeptides
What reactions would form a polymer via condesation
Carboxylic acid/Acyl chloride + Alcohol > Ester + Water/HCl
Carboxylic acid/Acyl chloride + Amine > Ester + Water/HCl
What are the 2 monomers used to make terylene
.Ethane 1-2 diol
. Benzene 1-4 dicarboxylic acid
What are the 2 monomers needed to form Nylon 6-6
.Hexanedioc acid
. Hexane 1-6 diamine
What are the 2 monomers needed to form Kevlar
. 1-4 diamino benzene
. Benzene 1-4 dicarboxylic acid
Give an example of when polyamides/esters can be formed from one monomer
4 hydoxybutanoyl chloride
Why can condensation polymers be broken up
They can undergo hydrolysis, this is because they have the prescence of polar bonds that attract the attacking species as nucleophiles and acid, they are biodegradable
How do you hydrolyse a polyester/amide
Use an acid or alkali, this will result in the original monomers forming, carboxylic acid or amine group may be in salt form depending on whether the conditions are alkali or acidic
What is the intermolecular bonding between the condensation polymer chains
They have permanent dipole forces between the C=O groups in the different chains aswell as van der waals, the polyamides have hydrogen bonding between the C=O bond and the N-H bond in the different chains which allows them to have a higher boiling point.
How do you dispose of polymers
.Landfill, most polymers are non biodegradable and take many years to break down
.Inceneration, rubbish is burn and the energy produced is used to generate electricity, some toxins can be released on incineration, greenhouse gases emitted
.Recycling- Saves raw materials, it is an expensive process, they can be only recylced into the same type, thermoplastics polymers can be melted down and reshaped