condensation polymers Flashcards
define a condensation reaction
2 small molecules react to make a larger molecule with the elimination of a small molecule (e.g: water)
define condensation polymerisation
joining of 2 monomers with 2 different functional groups
in an amine linkage what are the 2 functional groups involved
carboxylic acids
amines
what linkage is repeated in a polyester
ester linkage
- COO-
what reactants are needed to produce a polyester
a diol ( 2 x OH) and a dicarboxylic acid ( 2 x COOH)
what reactants are needed to produce polyamides
a dicarboxylic acid and an diaminoalkane ( 2 x amino groups)
in polyamides what type of linkage is repeated over and over again
amide linkage
-CONH-
what reactants are needed to make the polymer nylon 6,6
1,6 diaminohexane
hexane 1,6 dicarboxylic acid
what type of polymer are nylon and kevlar
polyamides
(condensation polymers)
why is kevlar strong
rigid chains and ability of flat aromatic rings to pack together held by strong intermolecular forces
give 3 uses for Kevlar
- bullet proof vests
- anti stab clothing
- oven gloves
give the 3 steps for identifying monomers of polymers
- start with repeating unit
- break the linkage
( at C - O for polyesters or C - N for a polyamide) - add back components of water for each ester/amide linkage
how many naturally occurring amino acids are there
20
why can polypeptides be described as polyamides
may be made from single or lots of amino acid monomers
each amino acid has a amino group and a COOH group so amine group of one a/a reacts with COOH group of another a/a
and a molecule of water is eliminated
= condensation polymer
why are poly (ethene) and poly (propene) not biodegradeable
long chain alkane molecules
these are unreactive due to strong non polar C - H and C - C bonds so nothing in natural environment can break them down
disposed of by incineration or landfill
