Plastic Bottle Manufacturing Process - How Plastic Bottles are Made

A plastic bottle is a common enough item used among all households and one with which you are well acquainted with! But have you ever wondered about the process that a manufacturer chooses to make plastic bottles? You might be questioning this again and again how the plastic bottle manufacturer chooses the material and how plastic bottles are created during the manufacturing process.

Bottles up! It’s time to learn about the manufacturing process of your favorite drink.

 

Which material is used by plastic bottle manufacturers?

Though there are a wide array of bottles and containers made from plastic, including water bottles, soda bottles, honey, and food containers. Many plastic bottles used are particularly made with Polyethylene Terephthalate that is PET, this is favorite for producing any type of bottle that is lightweight, strong. and durable- useful when bottles are used for foods and drinks. PET is one of the most popular choices among consumers as well as manufacturers, placing itself well ahead of its competitors, aluminum, steel and glass.

The material, PET, is a naturally transparent type of thermoplastic that has wide applicability in the bottling and packaging industries. Although the manufacturing procedure may vary and the process may be based on proprietary methods. However, the basic method for producing bottles is universal.

 

Why manufacturers choose thermoplastic PET for the process?

The main feature that sets it apart from other plastics is that these can go through numerous melt and solidification cycles without any significant degradation. Other than that, these are recyclable, that means, through innovation the industries using PET are constantly improving their environmental record further by redesigning and reusing the plastic bottles.

The manufacturers design and produce the PET bottles for one-time purpose only, for packaging. Although the FDA has approved PET bottles for single-use and reuses as well.

 

How are PET bottles made?

The PET bottles are a form of thermoplastic that are usually supplied in the form of small pellets or sheets of PET resins. The resins are then heated to a molten liquid that can then be easily extruded or molded into almost any desired shape using various manufacturing processes. As mentioned, these can be recycled and redesigned into the desired product. To simply put, the manufacturing process of PET plastic bottles is completely reversible, as no chemical bonding takes place, which makes recycling, melting, and reusing thermoplastics feasible.

 

There is an array of different methods that are used to make PET plastic bottles, but we have listed below the most common method:

 

Step 1: Building a preform, till then PET is initially heated.

The mold is prepared to make a preform that includes the bottle’s characteristics and the screw top. The PET is initially heated into a molten state, before it is placed into the preform or a tube-shaped mold. This process is most likely preferred among manufacturers, known as injection molding. This molding process has to be performed quickly. Once PET takes the required shape it is referred to as a parison. This method saves a lot of energy as the material has only to be heated once.

 

Step 2: Cold preform and reheated

The parison is then cut to the correct length and then it has to be quickly cooled down and removed from the mold. The preform is injected into the shape and then heated back up and placed into a mold that is shaped like the bottle that has to be manufactured. Though this method is not very efficient but the molecule inside of the PET then polarizes and this process leaves us with a plastic bottle.

 

Step 3: Cooled and trimmed

The bottle is then cooled down instantly and removed from the mold otherwise it can lose the shape. There are several different methods among plastic bottle manufacturers to cool the bottle down, some do this by circulating cold water through the mold and others choose to elect to fill it with a shot of air at room temperature. At last the excess material is trimmed away and added to regrind if some flashing occurs at the bottle seems.