3
(+1)R concept
In solving plastic waste disposal problem
by Lee Jo May
Universiti Sains Malaysia
Sept 20, 2010
Overvie
w
problems derived from irresponsible

Discuss
waste disposal
plastic

Explain and highlight the contribution of 3(+1)R concept
in plastic waste management

Focus on development of (+1)R – Introduction to
biodegradable plastic
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PLASTIC PLASTIC PLASTIC PLASTIC PLASTIC PLASTIC PLASTIC PLASTIC PLASTIC PLASTIC
1. Plastics low
biodegradability
2. Limited landfills
3. Expanding
population and
industrialisation
WASTE
WASTE
WASTE
WASTE
WASTE
WASTE
WASTE
WASTE
WASTE
WASTE
3
PLASTIC EARTH
3 (+1 ) R Concept
Reduce
Introduce
3R
Redevelop
biodegradable
Reuse
insufficient
plastic
Recycle
3 R 2 reasons
(+1) R
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Redevelop

Non-degradable
Degradable

‘Biodegradable’ material definition :
‘a
material capable of undergoing decomposition into
carbon dioxide, water, methane, or biomass resulted
from the enzymatic action of microorganisms, which
can be measured by standardized tests, in a specified
period of time reflecting available disposal condition. ’
-ASTM-
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Identifying
biodegradable
polymers
Type I
Natural occurring
polymers
Type II
Polymers with
hydrolysable
backbone
Eg. :
Eg. :
Cellulose
Polyesters
Type III
Copolymers or
blends of nondegradable polymers
with Type I or II
polymers
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Life cycLe of ‘GReeN’
biodegradable plastic material
NATURAL
RESOURCES
CARBON DIOXIDE
& WATER
(CO2 + H2O+
C residue)
DISPOSABLE
HARVEST
PRODUCT
BIODEGRADABLE
POLYMER
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……BioDeGRADATioN……
Increasing Time
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Conventional vs Biodegradable
Composition
Conventional
plastics
Polyethylene,
polypropylene
Biodegradable
plastics
Starch, Cellulose,
polyesters
Bad
Excellent
Commonly cheap
Mostly expensive
Application
Wide variety
Raw materials
Unrenewable
Limited
applications
Renewable
Example
Biodegradability
Price
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Conclusions

3R is insufficient to overcome problems of plastic
waste accumulation.

3R & (+1)R [redeveloping plastic materials] should
coexist.
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