Plastic that can trigger and accelerate the degradation

 Plastic bags are commonly used by the
consumers because it is much stronger and more elastic to use than the paper.
According to R. Dilli (2007) there are two types of plastic bags, the singlet
and the boutique bags. “Singlet” bags are made of high density polyethylene
(HDPE) and “boutique” bags are made of low density polyethylene (LDPE). Singlet
bags were mainly used in supermarkets, fresh produce and take-away food
outlets, and other non-branded applications. While the boutique bags were
generally used by branded and stores that selling higher-value goods such as
department stores, clothing and outlets. High Density Polyethylene bags is
manufactured from ethylene, a by-product gas or oil refining. J. Sevitz, A.C
Brent, and A.B Fourie (2003) stated that it involves extruding and blowing
pelletised HDPE (with 4.7% coloured pellets). The HDPE is polymerized from
ethylene. The ethylene feed consists of 15% propane gas, 67% ethane gas, and
18% from other C2 hydrocarbons. The propane is a product of the refining of
crude oil and the ethane comes from the coal gasification processes. Like their
counterpart, Low Density Polyethylene bags are also manufactured from ethylene,
a by-product gas or oil refining. In 2005, Australians used 3.92 billion
lightweight single use high density polyethylene (HDPE) bags, 2.14 billion of
these came from supermarkets, while the others were used by; fast food
restaurants, service stations, convenience stores, liquor stores and other
shops. Most of these go to landfill after they are used and some are recycled.
According to K. James (2000), there are different degradable plastic bags
depends on their breaking down process.. First is Biodegradable polymers are
those that are capable of undergoing decomposition into carbon dioxide,
methane, water, inorganic compounds or biomass. Second, Compostable polymers
are those that are degradable under composting conditions. Third,
Oxo-biodegradable polymers are those that undergo controlled degradation
through the incorporation of ‘prodegradant’ additives (additives that can
trigger and accelerate the degradation process). Fourth, Photodegradable
polymers are those that break down through the action of ultraviolet (UV)
light, which degrades the chemical bond or link in the polymer or chemical
structure of the plastic. And lastly, Photodegradable polymers are those that
break down through the action of ultraviolet (UV) light, which degrades the
chemical bond or link in the polymer or chemical structure of the plastic.
Since it is not renewable or reusable, after being used, it was just being
thrown away into the street, creeks and into the oceans.