Plastics are synthetic materials obtained by polymerization reactions from petroleum derivatives. They are organic materials, just like wood, paper or wool. The raw materials used to produce plastics are natural products such as coal, natural gas, cellulose, salt and, of course, petroleum.
The term "plastic" comes from the Greek "plastikos" which means that it can be molded. Plastics have different properties that allow them to be molded and adapted to different shapes and applications, such as packaging, clothing, utensils, medical devices, household appliances, means of transportation, among others.
According to their characteristics, there are two families of plastics:
- Thermoplastics: these are easily recyclable plastics since they melt when heated and can therefore be molded repeatedly without altering their original properties too much. The best known thermoplastics are: LDPE, HDPE, PP, PET, PVC, PS, EPS (expanded polystyrene) and PC (polycarbonate).
- Thermosets: These are difficult to recycle because they are made up of polymers with chemically linked chains that require the destruction of their molecular structure in order to melt them, and this leads to a major alteration of their original properties. There are different thermosets such as: phenolic resins, ureic resins, etc.
Plastics have made a great contribution to solving many of society's needs, but the growth of cities and the number of inhabitants has significantly increased the amount of waste generated and the demand for raw materials. One of the solutions is to considerably increase the incorporation of recycled material in final products and minimize industrial and household waste.