6.2.3 condensation polymers (polyesters and polyamides)

Addition polymers

* give the monomers which join to form addition polymers
* how to make poly(propene)
* give properties of (poly)alkenes
* how would you draw poly(alkane)

* alkenes
* need monomer propene and add a few together
* are saturated molecules, normally non-polar =) hence unreactive (don’t degrade well in landfill
* repeat units

Condensation polymers

* name 2 main types
* what is a condensation polymerisation?
* the link determines the type of polymer produced

* condensation polymers are comprised of polyamides and polyesters
* where 2 different monomers with at least 2 functional groups react together. during reaction a link is made and water is eliminated
* 1) polyamides: formed by reacting diamines and dicarboxylic acids

2) polyesters: formed by reacting a diol and dicarboxylic acid together

polyamides

* how are they made?
* why do we have to use these compounds?

* by reacting dicarboxylic acids and diamines together = amide links formed when dicarboxylic acids react with diamines
* as they have functional groups either side which allows for chains to be formed

HO-CO-R-CO-OH + H-NH-R-Nh-H -)

HO-CO-R(-CO-NH-)R-NH-H + H2O

Nylon 6,6

* nylon is collective name for?
* what is special about these saction?
* what properties does this section give Nylon?
* how is nylon-6,6 made?
* how are nylons named?

* polyamides that contain aliphatic hydrocarbon sections
* sections are non-polar and free to rotate and twist
* makes nylon strong and flexible (used in ropes, carpets, clothes )
* 1,6-diaminohexane and hexanedioic acid
* by numbering the amino group first then the acid group.

kevlar

* what is it?
* what are it’s properties
* how is it made?

\

* is a polyamide used in bulletproofvest, car tyres…
* lightweight, strong and fire-resistant
* 1,4-diaminobenzene and benzene-1,4-dicarboxylic acid and water is eliminated

polyesters

* how are they formed?

* by reacting dicarboxylic acids and diols together = ester links are formed when dicarboxylic acids react with diols

terylene

* what is it?
* how is it made?

* is a polyester that is used in plastic drinks bottles, sheeting and clothes. ( acronym PET)
* from benzene-1,4-dicarboxylic acid and ethane-1,2-diol

hydrolysis

* why is it used?
* what is it?
* what do you get when you hydrolyse a polyamide?
* How do you determine the monomer units produced?

* condensation polymers can be hydrolysed (split using water) to produce the original monomers.
* it’s the reverse of polymerisation
* using a water molecule, you get a dicarboxylic acid and a diamine, breaking the aminde
* 1) break the bond in the middle of the amide or ester link of the repeat unit

2) add OH and H to each of the monomer units

addition polymers

* how can we work out the monomer from the polymer chain?
* monomer can be found in addition polymer how?
* How do you work out the repeat unit from Rrom the monomer?

* by finding the repeat unit which will always have at least 2 carbon backbones
* remove bonds between the repeat units and inserting double bond between the 2 carbon atoms
* draw the 2 carbon atoms and instead of double place a single bond.

condensation polymers

* we can work out the monomer from the polymer chain by
* how can condensation polymers be more complicated?
* condensation polymers can be formed from 1 type of monomer in some cases

* 1) by finding the repeat unit. we can look for an amide link (HN-CO) or an ester link (CO-O)

2) break these links and add H or OH to either end of both molecules.
* they can contain amide and ester links (molecules with amine and alcohol groups can react with dicarboxylic acids to form more complicated condensation polymers)
* molecules with carboxylic acid and either an alcohol or amine group can react with itself to form a more complicated condensation polymer.