In the life of a modern person a large place is occupied by various products made of plastic. One of such widely used materials is polystyrene. It is an excellent building multifunctional material that is excellent for any insulation work.

Types and properties of polystyrene

Polystyrene is a product of styrene polymerization, which, in turn, is a monomer synthesized from petroleum. The industry produces polystyrene in the form of granules having a size of from 2 to 5 mm. Polystyrene is a solid polymer characterized by the following properties:

thermoplasticity; low thermal conductivity; moisture resistance; the presence of good dielectric properties; transparency. The main negative properties of polystyrene are: fire hazard; fragility; environmental insecurity. The most commonly used polystyrene is general purpose (PS), high impact polystyrene (UPS) and polystyrene foam. Due to its physical properties and the fact that ordinary polystyrene is easily machined, it is used in various sectors of the economy: in medicine, in the food industry, in agriculture, in the electrotechnical industry, in construction.

High impact polystyrene is obtained by adding rubber to styrene during polymerization. This increases the impact strength of polystyrene. In addition, the fragility and transparency of the material is reduced. From this material you can make various useful products.

Polystyrene foam is obtained by saturating the original polystyrene with air. The resulting material has a number of additional properties, such as high thermal insulation. Due to this property, polystyrene foam panels are widely used to provide thermal insulation for various buildings. A variant of foamed polystyrene is extruded polystyrene. This type of foamed polystyrene is obtained by mixing polystyrene granules at elevated pressure and temperature using a foaming reagent. This mixture is extruded using an extruder. The properties of these two types of foamed polystyrene differ in some parameters from each other, but their main characteristic of thermal insulation is close. At the same time, during construction it is recommended to use ordinary expanded polystyrene for external wall insulation, and extruded polystyrene for internal insulation.

Polystyrene recycling

Recycling of polymeric materials is an important issue for the preservation of ecology. By recycling polystyrene, you can not only maintain the ecological purity of nature, but also make a profit. The technology for processing waste polystyrene should be selected depending on the type of waste, location and amount of waste. The following methods are available for the processing of polystyrene: mechanical processing; recycling; energy recovery; filling the grooves; depolymerization.

Mechanical processing consists in grinding pure polystyrene and mixing it with granules in the development of new products from polystyrene. If polystyrene is mixed with other plastics, then it can be used for pressing various products such as benches or columns for the fence. Since obtaining secondary polystyrene is not always economically feasible, it is sometimes more useful to use shredded waste polystyrene to improve soil structure or as a filler in the manufacture of building materials. In some cases, the processing of polystyrene is energy recovery, that is, burning waste and using heat to generate electrical or mechanical energy. In this case, it is necessary to take into account the existence of a system for controlling the release into the atmosphere of harmful substances generated during combustion.

A possible use of crushed polystyrene is to fill various geological recesses on the ground. This prevents the accumulation of harmful gases or pollution of groundwater. Specialists from the United States proposed a new method for recycling polystyrene waste. This method involves a process in which polystyrene, interacting with a catalyst, is converted into a monomer, styrene. Polystyrene can be made again from secondary styrene. The difficulty of using this process is costly.