There is approximately more than sixty million tons of polyethylene foam produced in the world every year. In the United Kingdom, the foam is commonly known as polythene while in some parts of the world, it is mostly abbreviated as PE.
The polyethylene is produced when the ethylene is subjected to a process known as polymerization. Like most polymers, the polyethylene is composed of large chains of ethylene and has a corresponding molecular weight measured in the millions. If you want to create polyethylene that has different densities and with different material properties, you will need different catalysts in the process of polymerization. One common example of this is the high density polyethylene (HDPE). The HDPE is produced using the chromium as a catalyst. The catalyst disables the branching of the molecular chains and enables the material to have a higher density.
Characteristics of polyethylene
Polyethylene is used widely for nautical purposes since it is very buoyant. Most kinds of polyethylene are not abrasive. They can be made as insulators, are inert to grease solvents and water when applied at normal temperatures, are ozone friendly and are free from the harmful CFC. They are also odorless, can be recycled and do not weight that much. Most types of polyethylene are approved by authorities to be used in the food industry.
The polyethylene is evidently present in almost every type of packaging. It is used to wrap different components of computer, furniture, sporting goods, clothing, electronics, frozen foods, signs, plants, metal products and others. It is conveniently available in different forms which you can use successfully to maximize thermal insulation or minimize static. The polyethylene is resistant to mold attack and bacteria and is also resistant to tear. The use of polyethylene is very economical in that it is one of the cheapest fabricated materials though it may not be as cheap as other raw materials since the process of polymerizations consumes a considerable amount of energy. If you use polyethylene as your packaging material, you should be ready with a relatively higher distribution cost since the polyethylene material cannot be readily compressed during shipment.
As a thermoplastic polymer, the polyethylene consists of long chains of hydrocarbon. For the glass transition and the melting point to be visible, it will have to be dependent on the molecular weight and the crystallinity of the substance. These usually occur at varied temperatures and will depend on how strong the type of polyethylene is. The melting point for commercial grade polyethylene as well as high density ethylene is at the range of 120 to 180 degrees Celsius. While the melting point for most average and low density polyethylene material is at the range between 105 to 115 degrees Celsius (221 to 239 degrees Fahrenheit).