6.2.3 Polyesters and polyamides

Give 2 types of condensation polymers

• polyesters

• polyamides

What are polyesters and polyamides used as?

fibres in clothing

How many monomers is polyesters formed from?

1 or 2

What are polyesters formed from

• dicarboxylic acids and diol

• diacyl chloride and diol

• bifunctional monomer

What is lost when a dicarboxylic acid and diol join to form a polyester?

H2O

What is lost when a diacyl chloride and dio join together to form a polyester?

HCl

How do polyester monomers form together?

by the ester -COO bond

What is the backbone of the polyester chain formed from?

-COO bonds

Draw the polyesterification of a dicarboxylic acid and diol

Draw the polyesterification of a diacyl chloride and diol

How could a polyester be formed from one type of monomer?

using a bifunctional (e.g. carboxylic acid and alcohol)

Give an example of a polyester formed from one type of monomer?

PLA

What is the monomer of PLA?

lactic acid

Draw the esterification of PLA

How many monomers are polyamides formed from?

1 or 2

What monomers form a polyamide?

• dicarboxylic acid and diamine

• diacylchloride and diamine

• bifunctional group

How do monomers join together in polyamides?

amine -CONH- bonds

What is the backbone of the polyamide chain formed from?

amine bonds

What is lost when a dicarboxylic acid and diamide join?

H2O

Draw polymerisation of a dicarboxylic acid and diamide

What is lost when a diacyl chloride and diamine react?

HCl

Draw polymerisation of a diacyl chloride and diamine

How can a polyamide be formed from one monomer?

bifunctional (e.g. amino acid)

Draw the polymerisation of amino acids

What does the polymerisation of amino acids form?

polypeptide/polyamide

Why can’t addition polymers be hydrolysed?

polar C-C bonds

give 2 methods of hydrolysing polyesters

• acid-catalysed

• base-catalysed

What are the reagents for acid catalysed hydrolysis of polyesters?

aqueous acid

What are the conditions for acid catalysed hydrolysis of polyesters?

heat

What are the products of acid catalysed hydrolysis of a polyester?

dicarboxylic acid and diol

Draw acid catalysed hydrolysis of a polyester

What are the reagents of base-catalysed hydrolysis of polymers?

NaOH

What are the conditions of base catalysed hydrolysis of polyesters

heat

what are the products of base catalysed hydrolysis of polyesters

dicarboxylate salt and diol

Draw base catalysed hydrolysis of a polyester

What are the reagents for acid catalysted hydrolysis of polyamides?

aqueous acid

What are the products of acid ctalysed hydrolysis opf polyamides?

dicarboxylic acid and diamine

What are the products of base catalysed hydrolysis of polyamides?

dicarboxylate salt and diamine

What is a biodegradeable polymer?

a polymer that breals down completely into carbon dioxide and water

What does a biodegradeable polymer break down into?

carbon dioxide and water

What is a degradeable polymer?

a polymer that breaks down into smaller fragments when exposed to light, heat or moisture

Why are polyesters and polyamides biodegradeable?

they have polar bonds that can undergo hydrolysis

Give 2 examples of biodegradeable polymers

• PLA

• PGA

What is the use of PLA?

food packaging

What is the monomer of PGA?

glycolic acid

What is PGA used in?

self dissolving surgical stitches

What a photodegradeable polymer

a polymer with a C=O bond

Why are polymers that contain a C=O bond photodegradeable?

it absorbs light radiation causing the bond to break