What are plastic bottles made of?
Plastic water bottles have long been a part of our lives. We buy five-liter containers of clean water in stores and fill them in machines when the liquid runs out. But at the same time, we think little about what these bottles are actually made of and whether the material is safe.
The content of the article
What are plastic water bottles made of?
Progress is proceeding by leaps and bounds, so the production of lightweight PVC containers has long been put into production, despite the ardent protests of manufacturers of glass and aluminum packaging.
PET containers and the material for them were invented many years ago. However, industrial development lasts only forty years.
History of the material
Polyethylene terephthalate is the exact chemical name of the base that is used in the production of food containers. It is popularly called lavsan, thermoplastic or polyester.
The material was invented back in 1941 by the American enthusiast Nathaniel Wyeth. Bottles made from this type of plastic began to be produced only forty years later. At the same time, the inventor was awarded for creating strong, durable and relatively safe raw materials.
The main advantages that captivated manufacturers were light weight, strength and tightness. In addition, its cost was low in comparison with glass and aluminum. Production bottles does not differ in increased complexity and high cost.
Advantages and disadvantages
The differences between plastic bottles and glass and aluminum containers are obvious. They have a number of undeniable advantages:
- Accuracy of sizing in container production.
- Passivity in relation to food products placed inside.
- Possibility of repeated opening and closing.
- Resistant to pressure when placing carbonated drinks.
Various liquids can be filled inside the bottle. Including alcohol, oils or weak acids. In addition, they are easy to recycle and re-produce.
The main disadvantage of containers is considered to be excellent gas permeability. This indicates a significant reduction in the shelf life of carbonated products. Otherwise, it is a safe and inexpensive container.
Production Features
Industrial plants use granules, from which (if the technology is followed) the finest material is obtained. Initially, excess moisture is removed from them. There are special drying installations for these purposes, since this stage is extremely important.
When moisture enters, cavities and porosity of the material appear.
Next, the granules are melted and a coloring element is added. This is done to protect the future product from ultraviolet rays. Then preliminary blanks with threads are formed. Afterwards, the preforms are heated in an oven and sent for blowing to obtain the final product.
What are caps for plastic bottles made of?
The main condition for the production of stoppers is the ability to withstand several cycles of opening and closing the bottle. They are made from polypropylene or polyethylene, often a block copolymer.
These materials can withstand high loads and do not wear out during storage of a sealed bottle. In addition, they can subsequently be recycled by reusing them in the production of containers.
Recycled material is sold at competitive prices.
Plastic containers have long replaced glass and aluminum. They are practical and can be used several times, and then sent for recycling of secondary raw materials for a new release into industrial production.
