polymers Flashcards
Photo-degradable Polymers
breakdown when exposed to ultraviolet (UV) light
disposable shopping bags
Biodegradable polymers
made from natural and renewable resources
Synthetic bio-polymers
renewable resources but chemically engineered to break down more quickly
Oxo-degradable Polymers
Additives in these polymers cause the polymer to break down into a fine powder
carrier bags
Hydro-degradable Polymers
These polymers break down with exposure to water
Detergent pouches
Corn starch polymers
Starch-based polymers
straws
Potatopak
Potato starch mixed with cellulose
food trays
Biopol
Made from bacteria
film
Polylactide Acid (PLA)
Made from corn kernels
carrier bags
Polyhydroxyalkanoate (PHA)
Made from bacteria
slow release medical patches
Cellulose Acetate
Obtained from wood fibre
packaging
Lactide
PLA and cellulose based
slow release medication
Glycolide (Lactel and Ecofilm)
PLA and cellulose based
bags
Additives
degradation times reduced considerably
Cost
biodegradable polymers are more expensive to produce than conventional polymers
Implications
Biodegradable polymers can produce methane gas when they decompose in landfill
may leave behind toxic residue
need land to grow the crops to make them
cannot be recycled
Thermoplastics
polymers that when heated become plastic
tangled and weakly bonded polymer chains
Thermosets
polymers that when heated become rigid
strong cross links that form
Elastomers
able to be deformed and then return to their original shape
ABS – Acrylonitrile Butadiene Styrene
computer cases
PMMA – PolyMethyl MethAcrylate
Light units
PP - Polypropylene
Food containers
HIPS – High Impact Polystyrene
Toys
EPS – Expanded PolyStyrene
Packaging
