polymerisation

Question 1

what are condensation polymers

Answer 1

they form when a water molecule is removed from the species of a reaction

Question 2

what are the three main types of condensation polymers

Answer 2

• polyamide
• polyesters
• polypeptides

Question 3

how are polyamides formed

Answer 3

in a reaction between diarboxylic acid and a diamine. a moleucle of water is removed leaving an amide linkage (-CONH-)

Question 4

examples of polyamides

Answer 4

• nylon - 6,6 - made from hexamethlyenediamine and hexandioic acid
• Kelvar - made from 1,4-benzendicarboylic acid and 1,4-benzenediamine

Question 5

how are polyesters formed

Answer 5

are formed in a reaction between dicarboxylic acids and a diol, producing an ester linkage (-COO-)

Question 6

example of a polyester

Answer 6

Terylene (PET) - made from ethanediol and 1,4-benzenedicarboxylic acid

Question 7

polypeptides

Answer 7

formed from multiple amino acids. A single monomer can produce a polymer due to the presence of both a -NH and -OH group. peptide linkage (-CONH-)

Question 8

hydrolysis

Answer 8

Condensation polymers can be broken down into the constituent molecules by the addition of H2O. as water is attracted to polar regions of the polymer, the links can be broken down

Question 9

Features of condensation polymers and their uses

Answer 9

contain polar bonds e.g. esters & amide links. H bonding and dipoles form between separate polymer chains, holding them together in a strong structure, useful for bulletproof vests/ heat protective materials

Question 10

Why are polyalkenes (addition polymers) difficult to dispose of

Answer 10

are inert with non-polar bonds, so species in nature can’t break them down. They are not biodegradable and broken down by burning which produces SO2/CO, leading to acid rain

Question 11

How are polyesters and polyamides broken down

Answer 11

through hydrolysis due to the polarity within the polymer molecules. They are biodegradable and break down easily in nature by water or moisture. so are put into landfills as they gradually break down.

Question 12

how can some plastics be disposed of

Answer 12

recycling, saving natural resources and reducing the waste that must be put into landfills. It’s time-consuming process as plastic has to be sorted and washed before recycled