Chemistry - POLYMERS

Identify the 2 types of polymerisation

addition and condensation

in condensation polymers what is produced in addition to the polymer?

a small molecule such as water or HCl

identify the monomers in addition polymerisation

alkenes

identify at least 2 monomers that can take part in condensation polymerisation

diols, dicarboxylic acids, amino acids, diamines, dioyl chlorides

identify at least 2 addition polymers

teflon, poly(propene), poly(ethene), PVC, superglue, perspex

how does branching affect the melting point of polymers

lowers the melting point as the chains can’t pack as tightly together

what substance can be added to polymers to increase their flexibility

plasticiser

what type of polymer is terylene (PET)?

a polyester (condensation polymer)

what are the monomers of terylene (PET)?

ethane-1,2-diol and benzene-1,4- dicarboxylic acid

what monomers are used to produce polyamides

diamines and dicarboxylic acids

what type of polymer is nylon

a polyamide

what are the monomers of nylon

1,6- diaminohexane and hexane-1,6-dioic acid

what type of polymer is kevlar

polyamide

why is kevlar so strong?

the aromatic rings are planar so can pack tightly together forming many intermolecular forces. The H attached to the N atom can also form H bonds with the O atoms

what are the monomers of kevlar?

1,4-diaminobenzene and benzene-1,4-dicarboxylic acid

what are the monomers of polypeptides

amino acids

what process is used to break down condensation polymers

hydrolysis

give at least 2 advantages of recycling

reduces waste in landfill
conserves raw material - crude oil
cost of recycling lower than extraction/processing of raw materials
produces less CO2 than burning

give at least 2 disadvantages of recycling

collecting, sorting and processing more expensive than burning/landfill
plastic is often weaker than before and needs to be made into a different product
can get contaminated

what type of polymer is not biodegradable and why

addition polymers due to the strong non polar bonds (polyalkenes)

what advantage does incineration of polymers have?

energy can be used for heating or production of electricity

what type of reaction breaks down polyesters and polyamides?

hydrolysis

why can polymers only be recycled a limited number of times

the polymer chains get shorter and properties deteriorate; impurities can accumulate

what sort of link is formed between dicarboxylic acids and diamines when they polymerise

an amide link