Polymerisation Flashcards
what is a polymer ?
long chain molecules made from joining together many monomers
how does an addition polymer differ from a condensation polymer ?
addition polymers do not produce anthing else while condensation plymers form other small molecules
what monomers are used to make addition polymers
alkenes
molecules with C=C
what monomers are used to make condensation polymers
- dicarboxylic acids with diols
- dicarboxylic acids with diamines
- amino acids
examples of addition polymers
- poly(ethene)
- PVC
- poly (propene)
examples of condensation polymers
- polyesters (e.g. terylene)
- polyamides (e.g. nylon, Kevlar)
how biodegrabable are addition polymers ?
non-biodegradable (due to absence of polar bonds in the main chain (all bonds are C-C)
how biodegrabable are condensation polymers ?
biodegradable (due to the presence of polar C-N or C-O bonds in the main chain)
what are the types of condensation polymers ?
- polyamide
- polyester
- polypeptide
what is a polyamide and how is it formed ?
If a dicarboxylic acid reacts with a diamine, a polymer called a polyamide is formed and water is released.
What forces arise within the amine link of a polyamide ?
- have hydrogen bonding
- polar bonds which makes them more reactive
What forces arise within the ester link of a polyester ?
- permanent dipole-dipole attractions between the polymer chains due to the presence of a C=O polar bonds
How can condensation polymers be broken down ?
- Hydrolysis
- Condensation polymers can be broken down back into the constituent molecules by the addition of H2O.
- This is because water is attracted to the polar regions of the polymer meaning the links can be broken down.
How useful are condensation polymers and what are some uses ?
- Condensation polymers contain polar bonds such as those in the ester and amide links.
- Hydrogen bonding and dipoles can also form between separate polymer chains, holding them together in a strong structure.
- This makes the polymers very useful for things such as bulletproof vests and heat protective materials.