Polyethylene terephthalate is a polymer that is used in most countries to produce polyester fibers (70%), bottle resin (22%), film (6%) and engineering polyester resins (2%), but in Iran this polymer is more Used to make all kinds of drinking bottles.
Due to the high resistance of these bottles against breakage, temperature and penetration of gases, having a low weight and cheap price compared to other packaging materials such as glass and metal, the production of plastic bottles from this resin has been widely used.
Usages and properties of PET
Today, PET is mainly obtained by combining ethylene glycol with terephthalic acid with the help of heat and catalyst, which is a linear and solvent-resistant polymer. Special physical and chemical properties of PET such as high mechanical strength, joint strength, transparency, light weight, safety In terms of toxicity and impermeability to CO 2, it has been widely used in the manufacture of photographic films, beverage bottles, and fibers. It is also used in the production of BCF continuous fibers and industrial yarns and staples, POY textiles and clothing. It is also used as food packaging due to the ineffectiveness of PET in taste and heat stability.
Advantages and disadvantages of using PET
The advantage of using PET bottles is that the bottle cap can be easily opened and re-closed, and they are also light and inexpensive. More than 30 percent of the soil is degraded, and recycling PET and converting it into disposable products is a better solution.
Although these materials make up a small percentage of the total waste of the community (about 7%), but due to their low density, they contain a high volume of about 30% of the total waste. Typically, about 800 kg of waste is stored per cubic meter of landfill, while one cubic meter of landfill can only hold 35 kg of bottles.