Polymers

Question 1

whats the problem with plastics

Answer 1

• addition polymers/poly(alkenes) are non biodegradable due to the non-polar covalent bonds present between atoms in the polymers
• C-C bonds non-polar = not susceptible to attack by nucleophiles and therefore not easily hydrolysed

Question 2

what is a condensation polymer

Answer 2

• polymers formed from monomers with functional groups at both ends of the molecule
• e.g. diacid,diamine,diol,diacylchloride

Question 3

what are the two methods of forming a polyester

Answer 3

• condensation reaction between a diacid and a diol
• condensation reaction between a diol and diacylchloride

Question 4

when a polyester is formed from a diacid and diol what are the leaving groups from each monomer

Answer 4

• OH group lost from each acid end and H is lost from each alcohol end

Question 5

when a polyester is formed from a diacylchloride and diol what are the leaving groups from each monomer

Answer 5

• the H from the alcohol and the Cl from the acyl chloride

Question 6

what are the monomers of Terylene

Answer 6

• benzene-1,4-dioic acid and ethane-1,2-diol

Question 7

what are the two methods to form a polyamide

Answer 7

• formed in a condensation reaction between a diacid and a diamine
• formed in a condensation reaction between a diacyl chloride and a diamine

Question 8

what are the monomers used in forming Nylon-6,6

Answer 8

• hexanedioic acid and hexane-1,6-diamine

Question 9

what are the leaving groups of each monomer during the formation of a polyamide

Answer 9

• OH is lost from diacid and H lost from diamine
• Cl is lost from diacylchloride and H lost from diamine

Question 10

what is kevlar

Answer 10

• a polyamide used in bulletproof vests as it is extremely strong and lightweight

Question 11

what are the monomers of kevlar

Answer 11

• benzene-1,4-dioic acid and 1,4-diaminobenzene

Question 12

what is a bifunctional molecule

Answer 12

• molecule that has two different functional groups

Question 13

why are polyamides generally very strong

Answer 13

• hydrogen bonding occurs between the partially negative nitrogen,oxygen and partially positive hydrogen on adjacent chains

Question 14

why are polyamides and polyesters biodegradable

Answer 14

• the C-O/C-N bonds in the polymer chain are polar therefore the partially positive carbon can attacked by nucleophiles (the bond can hydrolysed)

Question 15

how are polymers disposed of

Answer 15

• poly(alkenes) can be burnt to produce carbon dioxide and water to produce energy however carbon monoxide and carbon could be produced if combustion is incomplete

Question 16

what are the advantages of recycling polymers

Answer 16

• almost all plastic is from crude oil so recycling stops overusage of crude oil as well as saves the energy that wouldve been used to refine it
• reduces landfill

Question 17

what are the disadvantages of recycling polymers

Answer 17

• plastics need to be collected, transported and sorted which uses energy and manpower which is expensive