The main challenge of modern polymer science is to search for ways of further development of polymer civilization, which obviously includes living organisms on the Earth, without harmful consequences for civilization and the planet in its entirety. The review considers approaches to handle the problem of environmental accumulation of plastic waste. Promising trends in the development of polymer technologies, which can significantly reduce the amount of waste produced, are highlighted. Separate Sections address original methods of additive manufacturing technologies, such as the extrusion printing technique to produce multilayer films, 3D printing by using high-temperature polyimide materials, new functional siloxane oligomers and hydrogels for medical uses. Much attention is paid to the development and applications of biodegradable materials in medicine, packaging industry and agriculture. An analysis of the European strategy for plastics and plastic disposal demonstrates that it has a number of limitations due to high energy requirements and changes in Earth's carbon balance. The modern approach to plastic waste management free from these shortcomings is briefly outlined. Bibliography — 1233 references.

The main known patterns of thermal and/or catalytic destruction of high-molecular-weight organosilicon compounds are considered from the viewpoint of the prospects for processing their wastes. The advantages of using supercritical fluids in plastic recycling are outlined. They are related to a high diffusion rate, efficient extraction of degradation products, the dependence of solvent properties on pressure and temperature, etc. A promising area for further research is described concerning the application of supercritical fluids for processing the wastes of organosilicon macromolecular compounds.

Recycling of plastic waste, in particular polypropylene, represents one of the most pressing challenges facing humanity. Despite the promise of chemical methods for recycling polypropylene, they usually require a high temperature and are energy-intensive. In this work, we investigated the oxidative thermolysis of polypropylene in aqueous media. This approach rendered it possible to carry out the decomposition of the polymer at a comparatively low temperature (150 °C). It was shown that among the tested, the most promising aqueous medium for the decomposition of polypropylene is water saturated with gaseous oxygen at an elevated pressure (14 bar) and at a temperature of 150 °C. In such an environment, polypropylene was converted mostly to acetic acid (up to 1.3 g/g acetic acid to starting polypropylene mass ratio). Moreover, methanol, formic acid, and propionic acid were also detected as the products. Finally, the applicability of the proposed recycling method to real polypropylene waste was shown.

This review considers the key advantages of using supercritical carbon dioxide as a solvent for systems with organosilicon compounds. Organosilicon polymeric materials synthesis as well as the creation and modification of composites based on them are discussed. Polydimethylsiloxane and analogues used as polymerization stabilizers and nucleation promoters in pore formation processes are analyzed as well.