WHERE DOES THE PLASTIC COME FROM? HISTORY AND TYPES - CHEMISTRY - 2025

The plastic comes, mostly, from the distillation of petroleum. Plastics are obtained through the polymerization of compounds derived from petroleum and natural gas. The plastics industry uses 6% of the oil that passes through refineries.

Plastics have properties that other materials do not have; they stand out because they have little weight and little color, and great resistance to environmental degradation.

For these reasons it is that they occupy a prominent place in the development of different industries, such as containers and packaging, telecommunications, transportation, construction, medicine and household appliances, among others.

History

The first of the products considered plastic appears in the year 1860 as a result of a reward made by a manufacturer of billiards.

That reward was $ 10,000 for whoever submitted a replacement to make the billiard balls. Until then, these balls were ivory.

John Hyatt dissolved cellulose in a compound of ethanol and camphor. The result obtained was celluloid, which would be very useful in the development of the film industry.

In 1909, the chemist Leo Baekeland synthesized a polymer from molecules of phenol and formaldehyde. This is how Bakelite was created, the first fully synthetic plastic in history.

Types of plastic

There are three types of plastic: thermoplastic, thermo stable, and elastomer.

1- Plastic thermos

Its macro molecules are freely arranged and intertwine. The most widely used plastics belong to this group. They are subdivided into five different types:

- Polyethylene (bags, containers).

- Saturated polyester (bottles, food containers).

- Polystyrene (protectors for packaging, insulators).

- Polyvinyl (water and gas pipes, electrical insulators).

- Polypropylenes (boxes, cases with hinged lids, syringes).

2- Thermo stable

In thermoset plastics, the macro molecules intersect to form a closed mesh network. They are divided into four classes:

- Phenols (electrical insulators, socket bases, switches).

- Souls (plugs, switches, panel covering).

- Polyester resin (boats, swimming pools, fibers).

- Epoxy resin (sports equipment, aeronautics, adhesives).

3- Elastomer

This kind of plastic has its macro molecules arranged in the form of a mesh network with few bonds. The following subtypes are included in this category:

- Rubber (tires, hoses).

- Wetsuits (knee pads, diving suits, straps).

- Polyurethane (foam rubber, fenders, artificial leather).

- Silicones (prostheses, probes, medical tubes, hermetic closures).

Classification of plastics according to their origin

Natural

These are the ones that do not need a laboratory process to be produced, since they are composed of natural substances. They come from animals or plants. An example is rubber.

Semi synthetic

The semi synthetics are those that, although the raw material comes from nature, are treated under chemical processes for their use. Celluloid is an example.

Synthetics

Synthetics are the plastic substances that are obtained through the polymerization of some simple molecules. This process is carried out in factories and laboratories. An example is polyurethane.

Three main manufacturing processes

The manufacture of the plastic articles is carried out by heating. This process is called thermoforming and can be in three different ways:

1- Vacuum

The plate is placed in a mold on a press, which adapts the plastic plate to its shape.

2- Pressure

In this case, the press is closed, giving the plastic the desired shape.

3- Mechanical

The machine itself is the one that molds the plastic. This method is possible thanks to the heat to which the plastic is subjected.

References

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2. "Where do plastics come from" in Plásticos Pama (June 2010). Recovered in September 2017 from Plásticos Pama at: pama15.wordpress.com
3. «Where does plastic come from? on GuideWhat. Recovered in September 2017 from GuideWhat at: guidewhat.com
4. «Origin of plastic» in Polimer Tecnic (April 2016). Recovered in September 2017 from Polimer Tecnic in: polimertecnic.com
5. «Plastics» in Slide Share (March 2010). Recovered in September 2017 from Slide Share at: es.slideshare.net
6. "How is plastic made" in How do I know? Recovered in September 2017 from How do I know ?: comose.net
7. "Plastic that comes out of the trees" in Xatakaciencia (August 2007). Recovered in September 2017 from Xatakaciencia at: xatakaciencia.com