International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Recycled plastics find more and more applications. In addition to recycled bulky products, the number and type of products also being used in polymer -mineral composites based on recycled PE and PP. One of the paving products sought by investors are traditional concrete blocks. However, they have their drawbacks, they are heavy, so their transport, logistics must meet stricter requirements, are products that are not very resistant to cracking as a result of impact, are fragile. Mineral-polymer products are the solution to such problems. Innovative compositions for their processing are a polymer – mineral mixture, containing mainly recycled material and mineral fillers (sand, ceramic waste dust). They are therefore products made of waste materials from recycling, recyclates and flakes of polymer materials.
The technology for producing the polymer – mineral composition is based on the extrusion and compression molding technology of the compositions obtained. Polymer compositions are secondary materials, after recycling in the form of recyclates, flakes, and waste plastics, mineral fillers, that is waste ceramic dust, sand as well as activating substances (dyes, plasticizers, adhesion compatibilizers, polymermineral wetting agents). As a result, plastic waste and ceramic waste that cannot be recycled will be effectively processed.
The sprinklers were made of various polymer materials (PP, HDPE) as well as characterized by different shape of working elements and a variable degree of contamination with mineral sludge. The research on the structure of manufactured materials and melt flow rate are presented. The influence of the type of material and mineral deposits on the process ability of the tested polymer-mineral compositions was determined.

Extrusion is one of the most important processes in polymer processing technology, just next to injection molding. The first extruder was invented and patented in 1879 by Matthew Gray, which used Archimedes screw in its design [1]. Since that time, constantly work on improving the work of extruders was carried out, which are implemented in two different ways, technological or constructional [2, 3, 4]. The constructional method involves both the modification of the screw design and the entire barrels of the plasticizing system. Evidence of the relevance of this issue may be the number of patents describing the classic and unconventional constructions of extruders [4]. The aim of the following work is to conduct a review of the contemporary construction solutions of the plasticizing systems barrels, whose applications were intended to improve the efficiency and effectiveness of the extrusion process. One of the most interesting solutions is the kinematic activation of the barrel wall in the metering zone by introducing a rotary sleeve in a plasticizing system whose rotational speed and direction can be freely modified.

Wasteless technology for processing of plastic waste and food packaging polymer, which is based on the usage of mechanical recycling as the most environmentally friendly way of plastic waste recycling has been developed. The introduction of various kinds of plastic waste, including plastic packaging waste, into sand cement compositions, allows, on the one hand, to dispose millions of tons of plastic waste and at the same time to reduce the negative impact of the last ones on the environment and humans. On the other hand, it allows substituting expensive fibreboard fibres by substantially cheaper polymeric waste, preserving and improving the properties of concrete mixtures, to which they were administered. The resulting product can be used as filler in a cement-sand mixture, which can significantly improve the physicomechanical, thermal and rheological properties of the product made on the cement-sand based mixtures.