Chemistry Reference
In-Depth Information
production.
2
The plastics industry revenue has grown an average of 3.5%
annually over the last 30 years. The five largest plastics produced are poly-
olefins [polypropylene (PP) and polyethylene (PE)], polyvinyl chloride (PVC),
polystyrene (PS), expanded polystyrene (EPS) or Styrofoam, and polyethylene
terephthalate (PET), which account for 70% of the total global demand, i.e.,
200million tons.
1,3
The USA plastics industry ranks third in revenue for all
USA industries, representing close to US$375 billion in yearly shipments,
and employs over 1million people.
The environmental problems created by plastics are enormous.
4
Over 10%
of waste generation is plastic, although some plastics are recycled, much is
disposed of in landfill. Plastic debris pollution has now accumulated in all
natural habitats. Plastics represent 60 to 80% of the total marine debris,
generated by improper waste disposal.
5
Most marine debris is generated
from land-based pollution, i.e., cigarettes/cigarette filters, food wrappers/
containers, (plastic) bags and beverage bottles. Ninety-six percent of the
plastic found in the North pacific consists of small pieces of plastic derived
from manufactured plastic products and pre-production plastic pellets (i.e.,
industrial pellets, virgin pellets, plastic resin beads, or nurdles).
6
Aside from
the mega- and macroplastic pollution problems there is evidence that
plastics are fragmenting in the environment to become minute indigestible
ingredients consumed by an ever wider range of organisms.
4,6
To enhance
the performance of plastics, a wide range of chemicals (plasticizers, flame
retardants, stabilizers, anti-oxidants, anti-microbials etc.) are added during
manufacturing. These chemicals are often toxic and may cause health
problems to a wide range of wildlife.
4
However, plastics do have some environmental advantages over other
materials: (1) less energy consumption is used in their manufacturing
(it takes 30% less energy to make polystyrene than paperboard containers);
(2) plastics are lighter than other materials thus require less fuel to transport
them; and (3) many thermoplastics can be recycled.
1
7.1.2 Scope of the Current Bio-plastic Industry
Bio-plastics can be defined as ''plastics that contain bio-based content, are
bio-degradable, or both''.
7
Given this broad definition, inclusion of any or-
ganic compounds in a plastic (such as wood-plastic composites) or deriving
a plastic from an organic feed source qualifies the product to be termed a
''bio-plastic''. Bio-plastics have the potential to reduce the long-term pol-
lution problems currently associated with petroleum-based plastics.
8
Much
interest exists in replacing petroleum-based (or petro-based) plastics with
bio-plastics.
8-12
Bio-plastic and bio-polymer usage is hindered by their price,
performance and availability.
7,10
Currently, less than 1% of total global
plastic usage is bio-plastics. Nevertheless, bio-plastic production is steadily
increasing worldwide. For example, the current USA bio-plastic market,
worth US$490million in 2010 and 26.7% of the global total, and is expected
to increase to 32.9% of the global total by 2015. The bio-plastic market is
