C11 - Polymers Flashcards
What is a carbonyl?
What is a hydroxyl?
What is a carboxyl?
carbonyl + hydroxyl
What is an amino group?
What is polymerisation? Name 2 types:
-many small molecules (monomers) join together to form large molecules (polymers)
-addition
-condensation
Draw the displayed formulae for the polymerisation of ethene:
What should you make sure to do in a displayed formula for addition polymerisation of alkenes?
-don’t draw the double bond
-write n
-end bonds should stick outside the brackets
How do you draw a repeating unit?
don’t draw the end brackets for repeating units, just the open end bonds
If it asks for the structure of a polymer though, then definitely draw the brackets and an n outside them
What is addition polymerisation?
multiple identical monomers covalently bonding together to form a polymer, where the repeating unit has the same atoms as the monomer as no other molecule is produced in the reaction
What is condensation polymerisation?
where many monomers polymerise to form a polymer, but also lose small molecules like water (hence the name condensation)
What is necessary for some monomers to undergo a condensation polymerisation reaction?
-each monomer must have at least 2 functional groups (eg a diol has 2 hydroxyl groups)
-there must be at least 2 different functional groups overall (eg carboxyl and hydroxyl)
What is an ester link?
the ester functional group that connects many dicarboxylic acids and diols together to form a polyester
Give an example of a diol and a dicarboxylic acid:
ethanediol
ethanedioic acid
Draw the general displayed formula for a condensation polymerisation between a dicarboxylic acid and a diol:
Coloured boxes represent the rest of the molecule
Name 3 naturally occurring polymers and their monomers:
-polypeptides (amino acids)
-DNA (nucleotides)
-carbohydrates (sugars)
A polypeptide is just an unfolded, non-functional protein (like just before protein synthesis ends at the ribosome)
Give an example of an amino acid:
glycine (only has one H in side chain)
What is an amino acid made out of?
2 functional groups (amino + carboxyl), and a side chain that determines what amino acid it is
What is a peptide bond?
the bond formed between 2 amino acids
Explain how amino acids react to form polypeptides:
Don’t write the general equation for this
condensation polymerisation
-H from amino group and OH from carboxyl group removed and form water
-exposed C from carbonyl group bonds to exposed N from previous amino group, forms a peptide bond
Also known as an amide bond/link
Write the general equation for the condensation polymerisation of amino acids:
note that the H₂O’s coefficient is just n, not 2n
This is because the end monomer’s groups don’t lose their OH and H to form another H₂O
