Biodegrabable Plastics

Question 0

Describe applications for biodegradable polymers in:

• packaging
• catering
• gardening
• medical and sanitary

Answer 0

• shopping bags , food trays , soft drinks bottles
• bowls and cutlery , disposable pots
• pots
• disposable gloves

Question 1

Define biodegradable. Why is it useful?

Answer 1

• designed to break down with natural processes such as sunlight and rain
• degrades under right conditions - biologically rich environment

Question 2

Define renewable raw materials

Answer 2

• majority of biodegradable plastics derived from these

- materials extracted from managed sources e.g when trees are felled new saplings are planted

Question 3

How are PHA polymers created? Otherwise knows as?

Answer 3

• produced naturally using bacteria - aid in fermenting plant sugars
• Biopol

Question 4

How are PHB polymers created?

Answer 4

• plastic harvested for bacteria - grown in cultures

Question 5

Full name of PHAs

Answer 5

Polyhydroxyalkanoate

Question 6

Full name of PHBs

Answer 6

Polybetahydroxybutyrate

Question 7

PHB applications

PHA applications

Answer 7

• used in packaging - similar properties to polypropylene

- medicine - dispersive fixatives - films , screws, bone plates, used to apply slow release medication

Question 8

Why are PHBs and PHAs useful?

Answer 8

• biodegradable
• stable in environment but fully compostible
• contact with micro organisms in soil - break down completely

Question 9

What are oxo - degradable polymers ?

Answer 9

• Have additives that promote short degradation times e.g less than 5 years
• break down into fine powder - from effects - heat, oxygen, moisture and mechanical stress
• more readily digestible by micro organisms

Question 10

Define photo-degradable polymers.

Answer 10

Break down when exposed to UV - more readily biodegradable

Question 11

What is bio - batch?

Answer 11

• helps conventional polymers break down more easily
• is an additive
• used with PE, PP ,PVC, PET or PS
• enable material to degrade in shorter period of time - less than 5 years - rather than 100 years for conventional oil based products

Question 12

Applications of water soluble polymers

Answer 12

• liquid detergent pouches - dispense detergent only when in contact with warm water
• laundry bags - dirty laundry held by material until placed in large washing machine - protecting e.g hospital staff

Question 13

Describe a weakness of biodegradable polymers

Answer 13

• more expensive than conventional polymers - cost of products more
• scales of production likely to increase - increasing interest - lower prices