polymers

what is a polymer

a molecule formed from many repeating “monomer” units

what are the two types of polymers

addition and condensation

when drawing repeat units do you need n

yes you do

name the addition polymer formed using ethene 

poly ethene 

what is a plasticiser

• A plasticiser is a substance added to a polymer to increase its flexibility by getting between the polymer chains.

• It pushes the chains further apart, weakening the intermolecular forces (like van der Waals or dipole-dipole forces) between them.

• This allows the chains to slide past each other more easily, making the polymer softer and more bendy

monomer and use of poly(chloroethene)

• what is it commonly known by 

• why is it suitable for its use

• PVC

• Monomer: Chloroethene 

• Uses:

  • Unplasticised: Hard, brittle material used for drainpipes and window frames 

  • Plasticised: Flexible material used for electrical cable insulation, flooring tiles, and clothing 

monomer and use of Poly(ethene)

• Monomer: Ethene

• Uses:

  • Plastic bags

  • Bottles

  • Washing-up bowls 

monomer and use of Poly(propene)

• Monomer: Propene

• Uses:

  • Crates

  • Ropes

  • Textiles

  • Moulded objects 

state the two ways of making a polyester

• with a dioic acid and a diol

• hydroxy carboxylic acid

when drawing the repeating structure of a polyester what is lost from each monomer to form the polyester

when drawing the repeating structure you lose the OH from the carboxylic acid group and the H from the alcohol group.

what is the equation in terms of n for the number of waters formed from condensation reactions forming polyesters

• what does n represent?

(2n-1) H2O

• n is the number of monomers in the polymer

state the two ways of making a polyamide

• dioic acid and diamine

• amino acid

how are esters named

the prefix from the alcohol and suffix from carboxylic acid.

• when naming methyl groups, count away from the ester functional group. this is the only instance where u can get 1-methyl…

when drawing the repeating structure of a polyamide what is lost from each monomer to form the polyamide

when drawing the repeating structure you lose the OH from the carboxylic acid group and the H from the amine group.

what is the IUPAC name for alanine

2-amino propanoic acid

what is the equation in terms of n for the number of waters formed from condensation reactions forming polyamides

(n-1) H2O

give the monomers properties and uses of Terylene

• monomer 1- Benzene-1,4-dioic acid

• monomer 2- ethane-1,2-diol

• properties- strong, resistant to corrosion, lightweight, high melting and boiling point (PDD forces)

• uses- used for water bottles

give the monomers properties and uses of Kevlar

• monomer 1- Benzene-1,4-dioic acid

• monomer 2- Benzene-1,4-diamine

• properties- very strong (hydrogen bonding due to N-H), High melting and boiling points 

• uses- bullet proof vests 

give the monomers properties and uses of Nylon 6-6

• monomer 1-  Hexane dioic acid

• monomer 2- Hexane-1,6- diamine 

• properties- strong (hydrogen bonding), high melting and boiling points 

• uses- in stretchy materials such as tights and parachutes

how are nylons named

they are named with the prefix “nylon” and then the two numbers are from the length of the carbon chain of each monomer

• side note- a nylon Is a straight chained polymer made of amines and something else. if it has a benzene It cannot be a nylon as it is not straight chained.

what is the type of link in this polymer

an ester link between an alcohol and carboxylic acid monomer 

what is the type of link in this polymer

amide link between amine and a carboxylic acid 

what is the type of link in this polymer

a peptide bond between amino acids

why are polyesters and polyamides not broken down by pure water?

the hydrolysis of polyesters and polyamides is too slow to be useful so an acid or base catalyst is required

• what are the products of acid and base hydrolysis of polyesters

• which is faster?

• Acid hydrolysis of polyesters breaks ester bonds using dilute acid to form a dicarboxylic acid and a diol (orriginal monomers)

• base hydrolysis uses a strong alkali (like NaOH) to form a dicarboxylic acid salt and a diol.

• Base hydrolysis is generally a faster reaction than acid hydrolysis. Both reactions are methods of breaking down polyesters into their original monomer components. 
  

• what are the products of acid and base hydrolysis of polyamides

• acid hydrolysis uses hot aq HCL and (2n-1) H2O to hydrolyse the amide links. this produces a dicarboxylic acid and an ammonium salt

• Hydrolysis with hot aqueous base (e.g., NaOH) and (2n-1) H2O. this forms a Dicarboxylate salt and a diamine

• the ammonium salt in acid hydrolysis forms a dative covalent bond with H+ ions to form NH3 but in the base hydrolysis it stays as NH2 as it doesn’t react with a base as it is already a base.

state the three ways of disposing of polymers

• landfill (quick and easy but polymers will be dug up in years to come)

• burnt/ incinerated- (quick and easy but relics toxic gas)

• recycling

advantages and disadvantages of recycling

advantages 

• reduces amount of plastic in landfill 

• conserves crude oil 

disadvantages

• expensive sorting costs 

• plastics must be collected, sorted and recycles which takes time and money 

state why addition polymers are non-biodegradable

• they are inert and contain a C=C

• they are non polar

• so not easily attacked by nucleophiles

state why condensation polymers are biodegradable

• condensation polymers have polar bonds

• these bonds can be hydrolysed by nucleophiles

can acyl chlorides form condensation polymers

yes