Exploring the biodegradability of plastics
AIM: To test the biodegradability of different plastics
HYPOTHESIS: That the plastic will break down about 80% in 21 days
METHOD:
1. Fill up half an ice-cream container with moist plastic.
2. Place identical sizes of plastics into the compost.
3. Record the pH of the compost with a damp piece of pH paper.
4. Record the temperature of the compost
5. Bury the container and monitor the condition of the plastics over 3 weeks.
MATERIALS:
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Compost
One ice-cream container
pH paper
5 samples of plastics
Balance
Thermometer
RISK ASSESSMENT: Microbes in the compost are dangerous. Don’t inhale them,
and wear gloves when handling the compost.
1.
2.
3.
4.
5.
Glad kitchen tidy bag- Light green
Glad garbage bag- Dark green
Multix tidy bags- white
Multix Apple Scented Kitchen Tidy bags- lime green
Supermarket bag- Blue
RESULTS:
Week 3:
pH: 7.5
pH: 7.5
Temperature: 15 degrees
Temperature: 17 degrees
By Emmie Guy
Page 1
Exploring the biodegradability of plastics
CONCLUSION: All of the plastics that were tested (Glad Kitchen Tidy Bag, Glad
Garbage bags, Multix tidy bag, Multix Apple Scented Kitchen bag and
supermarket bag) had no change, and are therefore degradable.
QUESTIONS:
1. The plastics had no change over the three weeks.
2. About 0-5% deterioration occurred at the most.
3. Compost was used as it contains more microbes than soil that eat away
at the plastic, compost also increases in temperature which speeds along
a reaction.
4. No, they are not biodegradable, it may be due to the conditions- not
having it outside in a proper bin, but no change was visible.
By Emmie Guy
Page 2