13.5 Polymerisation in alkenes Flashcards
Definition of polymer
long chain molecule made from of repeat units of smaller molecules joined together
Definition of monomer
small molecules that join together to make polymers
Definition of addition polymerisation
Formation of long chain molecules from lots of small molecules join in together with no other products
OR
Formation of a very long molecular chain, by repeated addition reactions of many unsaturated alkene molecules
What molecules undergo addition polymerisation?
alkenes
What is a repeat unit?
The specific arrangement of atoms in the polymer molecule that repeats over and over again
How is a repeat unit written?
In square brackets, with the letter n aftwr
What does the letter n show in addition polymerisation?
Shows that there is a large number of repeats
What is the general equation for addition polymerisation?
How are addition polymers named?
poly(name of molecule)
What conditions does addition polymerisation occur in?
high temperatures, high pressure
What are uses of poly(ethene)?
supermarket bags, shampoo bottles, children’s toys
What is the general equation for addition polymerisation of ethene?
What is the general equation for addition polymerisation of propene?
What is the monomer, polymer structure and repeating unit of poly(propene)
What is the general equation for addition polymerisation of chloroethene?
What is poly(chloroethene)?
PVC
What are the properties and uses of poly(propene)?
Properties: strong
Uses: Children’s toys, crates, fibres for rope, carpet
What are the uses of poly(phenylethe)?
Packing material, food trays and cups due to thermal insulting properties
What are the uses of poly(tetrafluoroethene) or teflon?
Coating for non-stick pans, permeable membrane for clothing, shoes, cable insulation
What is the monomer and polymer of propene?
What is the monomer and polymer of phenylethene (styrene)?
What is the monomer and polymer of tetraflurothene?
What are the benefits to the environment of biodegradable and photodegradable polymers?
-leave no visible or toxic residue
-used to make packaging, electronics, fuel-efficient and recyclable vehicles
What are the ways of disposing waste polymers?
-Recycling
-Combustion for energy production
-Use as organic feedstock
Why is PVC disposable a concern?
Not sustainable, when burnt it releases hydrogen chloride (HCl) which is corrosive and other pollutants like toxic dioxins
Why are polymers suitable for storing food and chemicals?
Lack a reactivity
How does recycling polymers help the environment?
Conserves finite foil fuels, decreases amount of waste in landfill
How is PVC recycling been improved?
Solvents are used to dissolve the polymer and high-grade PVC is then recovered by precipitation from the solvent, solvent is then used again
How can polymers which are difficult to recycle be exposed of?
They are incinerated to produce heat, generating steam to drier a turbine producing electricity
What is an advantage of feedstock recycling?
It is bale to hand unsorted and unwashed polymers
What is feedstock recycling?
Chemical and thermal process that can reclaim monomers, gases or oil from waste polymers
How are biodegradable polymers broken down?
By micrograms into water, CO2 and biological compounds
How are photodegradable polymers broken down?
Polymers are weakened by absorbing light to start the degeneration
What are examples of biodegradable polymers?
Starch, cellulose, contain additives
What are photodegradable polymers?
Oil-based polymers
What is the problem with using combustion to dispose of polymers?
Produces toxic gases such as CO, HCl
What is an advantage of using polymers made from natural foods?
Reduces the dependency on finite resources ,Photodegradable, Biodegradable
