How Is a Plastic Soda Bottle Made?

Plastic bottles are more widely used than their glass counterparts.

A plastic soda bottle has practical use in that we use it to hold our soda drinks and keep them fresh. Through understanding what manufacturers really use to form the plastics that make up the bottle, we can better understand why we need to recycle plastic bottles, as well as why they are more widely used than glass bottles.

History

Leonardo Da Vinci created the first form of plastic by combining animal glues with organic fibers and vegetable glues. Upon drying, the concoction formed a plastic-like substance. Alexander Parkes holds the credit for developing the first man-made plastic, in 1862; he named it Parkesine. Commercial use of plastic bottles began in 1947, bu they remained expensive until about the 1960s. Plastic's lightweight nature and low production costs gave it more practical use than glass bottles.

Function

Plastic soda bottles keep your soda fresh and carbonated until the first time you open them. Unlike a glass bottle, the plastic soda bottle can be dropped or mishandled during shipping without incident.

Features

Some plastic bottles have a brown or green tint in an effort to keep light out. Manufacturers use different resins and dyes to create new colors. The majority of bottles are clear and feature a broad, flat bottom that creates stability when one sets the bottle down. The midsection of the bottle usually consists of a smooth surface on which the manufacturer can paste the label.

Construction

High-density polyethylene is the most widely used resin in constructing plastic soda bottles. This impact-resistant and economical material provides a good moisture barrier. In the more widely used mold method, the manufacturer heats and molds the resin using two different methods. In one method, the manufacturer heats the resin and forms it onto a mold; when the resin cools, the mold is removed to reveal the formed plastic. In the other method---the blowing method---the manufacturer blows the resin into shape, much like glass blowing, while the resin has the desired temperature.

Benefits

Plastic bottles can help in the efforts of recycling. Recycling 1 lb. of plastic bottles saves approximately 12,000 British thermal units (BTUs) of heat energy. Also, using recycled materials uses 2/3 less energy than creating products from virgin materials. Recycled plastic bottles become outdoor decking, fleece jackets and carpeting, among other items. Every ton of recycled plastic saves about 8 cubic yards of landfill space.

References

• How is Plastic Made?