Download presentation
Presentation is loading. Please wait.
1
POLYMERS
2
Addition polymers Condensation polymers
4
Some definitions Polymer long chain molecule made from lots of small molecules joined together Monomer small molecules that join together in polymerisation Addition Polymerisation formation of long chain molecules from lots of small molecules joining together – with no other product Condensation Polymerisation formation of long chain molecules from lots of small molecules joining together – with a small molecule (e.g. water) released
5
http://users.argonet.co.uk/users/hoptonj/polymer.htm Addition polymers
6
n ethenepoly(ethene) polythene
7
Addition polymers n phenylethenepoly(phenylethene) polystyrene
8
Addition polymers n methyl 2-propenoatepoly(methyl 2-propenoate ) perspex
9
Addition polymers n methyl 2-cyanopropenoate superglue poly(methyl 2-cyanopropenoate)
10
Addition polymers n chloroethene PVC poly(chloroethene)
11
Addition polymers n tetrafluoroethene PTFE / Teflon poly(tetrafluoroethene)
12
Addition polymers n propenepoly(propene)
13
Addition polymers Catalysts are used for the polymerisation, and the exact mechanism depends on the catalyst and alkene (it is not electrophilic addition – it is usually catalytic addition). Polyalkenes are inert, although can burn. As they are inert, they are non-biodegradable.
14
Condensation polymers Condensation polymers are polymers formed from condensation reactions between monomers. A small molecule (often water) is produced as well as the polymer. Many natural polymers are condensation polymers, e.g. silk, starch and DNA. The two main types are polyesters and polyamides.
15
Polyesters Esters are formed on reaction between carboxylic acids and alcohols. Polyesters are formed when dicarboxylic acids react with diols. Polyesters are hydrolysed (in the presence of strong acid or a specific enzyme) into their constituent acid and alcohol, so they are bio- degradable.
16
Polyesters strong acid or specific enzyme - H 2 O
17
Polyesters strong acid or specific enzyme
18
Polyesters Kevlar
19
Polyesters Amides are formed on reaction between carboxylic acids and amines. Polyamides are formed when dicarboxylic acids react with diamines. Polyamides are hydrolysed (in the presence of strong acid or a specific enzyme), so they are bio- degradable.....
20
Polyamides strong acid or specific enzyme
21
Polyamides strong acid or specific enzyme
Similar presentations
© 2024 SlidePlayer.com. Inc.
All rights reserved.