POLIESTYRENE

Name: Polystyrene, PS

Real name: Polystyrene

Composition: C8H8

Family: Aromatic Polymer (Hydrocarbon)

Density: 1.05

Temperature range: -10°C/90°C

Owned by: Interessen‐Gemeinschaft Farbenindustrie AG (originally)

Polystyrene was first synthesized in 1839 by Eduard Simon, a German pharmacist who accidentally discovered the styrene polymerization process. Although its practical importance was not recognized at the time, decades later, with the rise of the petrochemical industry, it began to be studied with greater interest.

It was in the 1930s that the German company IG Farben began industrial production of polystyrene, finding applications in everyday objects thanks to its low cost and ease of molding. After World War II, polystyrene expanded globally, driven primarily by companies like Dow Chemical, which developed new production techniques and variations such as expanded polystyrene (EPS).

Since then, polystyrene has established itself as one of the most manufactured plastics on the planet and has played a fundamental role in the modernization of sectors such as packaging, construction, and the consumer goods industry.

Polystyrene is characterized by its rigidity, transparency, and ease of processing. It is a lightweight material with good dimensional stability and excellent moldability, allowing for the production of highly detailed, complex shapes. Its low production cost is another reason why it is used in a large number of consumer products.

One of its best-known variants is expanded polystyrene (EPS), which is obtained by injecting gas into the polymer, forming a lightweight foam structure with excellent thermal and acoustic insulation. Another variant is high-impact polystyrene (HIPS), which is achieved by modifying the polymer with rubber to improve its resistance to impact and fracture, making it suitable for more demanding applications.

Despite these advantages, polystyrene has significant limitations. Its mechanical strength is lower compared to other engineering plastics, and it has low chemical resistance to organic solvents. Furthermore, its environmental impact has been a matter of debate, as its natural degradation is very slow and its recycling, although possible, is not always carried out efficiently.

Polystyrene's applications are wide-ranging, thanks to its diverse shapes and properties. In the packaging sector, expanded polystyrene (EPS) is widely used in food trays, disposable containers, cups, plates, and insulated boxes due to its lightweight construction and insulating properties. It is also essential in the protective packaging of household appliances and electronic equipment, as it absorbs impacts during transport.

In construction, EPS is used in insulating panels, blocks, and thermal insulation systems that improve the energy efficiency of buildings and homes. Its ability to maintain temperature makes it an ideal material for air conditioning and protection against environmental changes.

In the consumer industry, rigid polystyrene is used in the manufacture of toys, office accessories, electronic product casings, disposable utensils, and furniture components. The HIPS variant has notable applications in household appliances, televisions, refrigerators, and products requiring greater impact resistance.

In the medical field, polystyrene is used in Petri dishes, test tubes, and other laboratory containers due to its transparency and ease of sterilization. However, its use in direct contact with food and beverages has been regulated in some countries due to concerns about monomer migration.