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Earthquakes are highly dangerous for all masonry structures, as they force high deformations that brittle building materials cannot withstand. The solution to such problems may be the use of flexible polyurethane-based technologies (composite strengthening, adhesives etc.). On the other hand, these technologies are relatively new and demand experimental prove, whether they would not lose their properties after being subjected to environmental conditions i.e. temperature fluctuations, humidity, chemically aggressive mortars, solar radiation etc. Herein, we discuss the aspect of durability of Sika PS polyurethane – the polymer used as both composite matrix and an adhesive in flexible protective technologies for masonry.

The removal of uremic toxins from patients with acute kidney injury is a key issue in improving the quality of life for people requiring peritoneal dialysis. The currently utilized method for the removal of uremic toxins from the human organism is hemodialysis, performed on semipermeable membranes where the uremic toxins, along with small molecules, are separated from proteins and blood cells. In this study, we describe a mixed-linker modulated synthesis of zirconium-based metal–organic frameworks for efficient removal of uremic toxins. We determined that the efficient adsorption of uremic toxins is achieved by optimizing the ratio between −amino functionalization of the UiO-66 structure with 75% of −NH2groups within organic linker structure. The maximum adsorption of hippuric acid and 3-indoloacetic acid was achieved by UiO-66-NH2(75%) and by UiO-66-NH2(75%) 12.5% HCl prepared by modulated synthesis. Furthermore, UiO-66-NH2(75%) almost completely adsorbs 3-indoloacetic acid bound to bovine serum albumin, which was used as a model protein to which uremic toxins bind in the human body. The high adsorption capacity was confirmed in recyclability test, which showed almost 80% removal of 3-indoloacetic acid after the third adsorption cycle. Furthermore, in vitrocytotoxicity tests as well as hemolytic activity assay have proven that the UiO-66-based materials can be considered as potentially safe for hemodialytic purposes in living organisms.

This paper presents an analysis of DSC/TG/DTG thermal studies for PA6 polyamide, coal fuels and polyamide composites with these materials. The test results are aimed at comparing the thermal effects and behavior of these materials under high temperature conditions and are the basics to know of the creation and use of polymer composites with various coal fillers.

The paper takes the analysis of thermal studies of different types of fuels. It allowed diversification of fuels depending on their composition and origin. Consideration of coal, biomass and waste (coal mule, sewage sludge) as fuel is nowadays an important aspect of energy in our country. It should be emphasized that Poland power engineering is based up to 95% on coal - the primary fuel. Mining industry, forced to deliver power engineering more and better fuel, must however, use a deeper cleaning of coal. This results in a continuous increase waste in the form of mule flotation. The best method of disposing these mule is combustion and co-combustion with other fuels. On the other hand, commonly increasing awareness state of the environment and the need to reduce CO2emissions energy industry have committed to implement alternative solutions in order to gain power, through, i.a.: development technologies use of biomass, which is one of the most promising renewable energy sources in Poland. The paper presents the results of research TG-DTA fuels made in an inert atmosphere.

Bone defect is one of the most important problem in orthopaedic therapy in which application of a biomaterial filling is necessary. Such material should be biocompatible, osteoconductive and porous as well as bioactive and compatible with the bone tissue. Subject of the work was investigations on nanocomposite membrane materials which consisted on synthetic polymer – poly-e-caprolactone (PCL) matrix and ceramic nanoparticles; tricalcium phosphate (TCP) and silica (SiO2) as a nano-filler. The nanocomposite membrane materials were produced by two-step dispersion of the nanoparticles in the biopolymer matrix. Characteristic of nanoparticles were made using transmission electron microscope (TEM), distribution of nanoparticles size (DLS) and specific surface area (BET). The morphology of nanocomposites and homogenous distribution of nanoadditives were made using scanning electron microscope with EDS analysis. Introduction of the nanofillers into the polymer matrix was monitored by thermal analysis method (TG-DCS). It was shown that the TCP nanoparticles affected stronger pore size and distribution but also the polymer structure (crystallity, physicochemical properties of the surface). Treatment of the nanocomposite samples in the simulated body fluid (SBF) induced some changes on the surface of the material containing bioactive ceramic nanoparticles. The results of the tests with SBF showed that the material is able to produce apatite structure on its surface (EDS analysis)

Aim of the work was production of nanocomposite polymer fibres containing ceramic particles using the electrospinning method and characterisation of morphology and bioactivity of the produced materials. The first stage of investigations consisted in preparation of a series of poly-L-lactide (PLA) solutions in various solvents mixtures in order to reach viscosity which would allow formation of fibres by the electrospinning method. Ceramic nanoparticles such as tricalcium phosphate (TCP) and silica (SiO2) were used as nanofillers of the polymer matrix. Their particle size distribution in the solvent solution as well as in the polymer suspension was determined by dynamic light scattering method (DLS). Morphology of the nanoparticles was observed using transmission electron microscopy (TEM). Distribution of the nanofillers in the nanocomposite fibres as well as diameter and morphology of the fibres was assessed using scanning electron microscopy with energy dispersive spectroscopy method (SEM/EDS). Effect of the nanofillers addition and the shaping method on the structure of the PLA matrix was investigated on the basis of the thermal analysis methods (TG/DSC) on the nanocomposite foils prepared by casting. It was revealed that the nanocomposite fibres showed apatite nucleation in in vitro conditions i.e. after incubation in SBF (37oC/ 3 days).