Plastic bags are
made from a ubiquitous polymer substance polyethylene. This kind of substance begins
as ethylene, and it is commonly extracted from natural gases, and then treated
to become the polymer, that forming long chains of carbon and hydrogen atoms.
These chains will be depending on what type of polyethylene is being used, but
they all help create various types of plastic bags. T. Lacoma (2017). A Polythene is produced from crude oil
and natural gas, two non-renewable resources is found underground, through a
process known as the tubular film process.
Basically there are many types
of polyethylene in creating plastic bags the HDPE, PETE, LDPE, LLDPE, PVC, PP,
and PS. The HDPE stands for high density polyethylene, it is the most and common
type of polyethylene used to create shopping bags. Polyethylene Terephthalate
(PET or PETE) is tough, clear and has good gas and moisture barrier compositions
that making it ideal for carbonated beverage applications and other food Tupperware
or containers. The LDPE is made from low density, branching chains of
polymer materials. This chain makes a very light, almost film like
plastic that is used to make the tear-away bags dry cleaners that are used for wrapping
cleaned clothes. The LLDPE is connected to linear low density polyethylene; these
plastics do not branch, but also didn’t have the same strength as HDPE
versions. It means that the shopping bags created from LLDPE plastics
need to be thicker and heavier weight that traditional grocery bags. PVC
is known as Polyvinyl Chloride which is excellent transparency, chemical
resistance, long term stability, good weather ability and stable electrical
properties. The flexible vinyl is used in wire and cable sheathing, insulation,
film and sheet, flexible floor coverings, and others. The Polypropylene (PP)
has excellent chemical resistance and it is commonly used in packaging.
Polypropylene is found in everything that are flexible and rigid packaging to
fibers for fabrics and carpets and consumer products. Then Polystyrene (PS) is
a versatile plastic that can be rigid. The general purpose of polystyrene is
clear, hard and brittle. Its clarity allows it to be used
when transparency is important, as in medical and food packaging, and in
certain electronic uses.
According to Rutan Poly
Industries, INC. (2014) to create plastic bags the process is similar to the
process for creating a book. There are two steps to make plastic bags the
process known as “extrusion” first step in making a plastic bag. An extruder is
used to heat the polyethylene plastic to a temperature of up to 500 degrees F
that can melt the pellets, and then the molten plastic flow
into machine and a die that determines the thickness that the bag will produce.
Afterwards, the plastic film is pushed into a bubble by the outside
air and through a cooling process. Then the film will cut into the appropriate
size and then placed onto a spindle. On the second step, once the plastic bag
is placed onto the spindle, it will go into conversion department. This group
of people will unwraps the film roll and cuts it with a heated knife that also
seals each of the sides of the bags together and conversion also adds some
characters on it. Lastly handles are cut out using a heat process, and logos,
designs and text is added to the bag. On
plastic bags the chemicals is in use are the commonly extracted from natural
gases and oil crude that involves the types of polyethylene.
on Plastic Industry over 150,000 plastic bags capable on two pallets. The same
number of paper bags would fill a 40ft truck. Plastic is also very strong.
Supermarket bags can hold at least 22lb of shopping. Some hold twice that.
Every year, each person consume 216 plastics and an estimated of 500 billion are
being used around the globe each year. It is commonly use for shopping and
being thrown for an average of 20 minutes. Daily Mail Reporter (2008) indicated
that the five trillion carrier bags produced each year start life as crude oil.
Demand is so high that 0.2% of the world’s oil is used to make them – about 60