Novosibirsk State Technical University (NSTU) is working on the use of recycled plastic for the production of building composites.
The widespread use of plastic products and packaging in various spheres of life has led to a rapid increase in the volume of polymer waste. In the modern world, more and more attention is being paid to the problem of their disposal. Today, the most common method of recycling polymer waste is their recycling.
"Plastic consumption is currently at a very high level, and if it is not disposed of, environmental problems cannot be avoided. We decided to use polymer waste as a raw material for the production of building composites. High—density polyethylene was recycled, mainly bottles from household chemicals. We had a composite made of three materials: polyethylene (used as a binder), sawdust (to reduce thermal conductivity and the possibility of obtaining thermal insulation materials) and cullet of various fractions (glass is now also a lot in solid household waste). The preparation took place as follows: plastic bottles were washed, cleaned of labels, cut into small pieces so that they fit into a cutting mill. They were crushed there, and we had ready-made plastic of the required fraction, which we later used. To obtain samples of the material, the hot pressing method was used: the required number of components were mixed, after which they were poured into a special mold, placed in an oven and waited for the mixture to warm up to the temperature of light melting of polyethylene. After 30 minutes, they pressed, then waited for the sample to harden, and took it out. The obtained samples were tested for water absorption, thermal conductivity, strength and density. As a result of the work, a material was obtained that can be used in construction for cladding buildings," said Natalia Osipova, a 1st—year undergraduate student at the Faculty of Aircraft at NSTU-NETI.
According to her, there are several advantages of using polymer waste as a raw material for building composites. Firstly, the environmental benefit is the solution to the problem of plastic waste accumulation (reducing their volumes in landfills and in natural ecosystems helps to reduce the negative impact on the environment). Secondly, cost reduction: recycling such waste into building materials can significantly reduce the cost of the final product. Thirdly, improved physical and mechanical properties: depending on the type of polymer waste, such composites may have good mechanical properties such as strength and hardness. Polymers can be added to concrete or asphalt to improve their water-repellent properties and increase durability. Polymer waste often has a low density, which makes it possible to create lightweight building materials. In addition, polymer materials such as polyethylene or polypropylene are resistant to moisture, chemicals and microorganisms, which increases the service life of building composites containing recycled plastic. Thus, the use of polymer waste in construction not only helps to improve the environmental situation, but also allows you to create functional, user-friendly and economical materials.
"Polymer waste can be used to produce various building materials such as tiles, panels, road coverings, insulation materials," adds Natalia.
In the future, the developers plan to increase the strength and thermal conductivity of the resulting material, and strengthen the adhesion of the composite components.
It should be recalled that the NSTU-NETI has proposed a technology for plastic recycling using wax moths.