system. Ziegler-Natta (ZN) catalysts generally dominate in PE and PP production, but they have their limitations when higher α-olefins are used for copolymerization. The disadvantages of ZN systems in this case are uneven and limited comonomer incorporation. The comonomer is incorporated randomly along the polymer chain, with a tendency to higher comonomer concentrations in the low-molecular weight fractions and less in the high molecular weight part. Further, ZN catalysts lead to broad molecular weight distributions (MWDs), which may be problematic with respect to the amount of extractable material.Higher-branched low molecular weight parts lead to a faster degradation which reduces the durability of the polymer material. Therefore, polyolefines with a homogeneous comonomer incorporation show beneficial properties concerning tensile strength, film transparency, and environmental stress cracking, which results in advantages for many applications, such as films and pipes. Metallocenes can tackle these requirements, as they can polymerize longer α-olefins (up to C26), yield narrow and homogeneous MWDs, and support comonomer incorporation of up to 20%. The demand for metallocene-based polyolefins, especially PE, is increasing significantly. The Various MgCl 2 -supported Ziegler-Natta (ZN) catalysts are synthesized with the intention to influence polymerization performance and 1-butene incorporation in an ethylene copolymer. Modifications are introduced during different steps in the synthesis process, namely support preparation, titanation, and catalyst workup. While multiple different effects are observed upon modification, heat treatment during titanation shows the greatest impact. Increasing the heat-treatment temperature increases polymerization activity. More importantly, the 1-butene distribution can be shifted toward a more homogeneous profile. The amount of 1-butene incorporated is similar to both for short-and for very long-chain molecules. This behavior has so far been known only from metallocene-based polyethylene and suggests that active sites are distributed more homogeneously in the ZN catalyst.

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The main requirement to the materials used to make membranes polymer electrolyte membrane fuel cells (PEM FC) is the combination of high proton conductivity and resistance to the FC operation conditions. Thus, the search for inexpensive and high-performance non-fluorinated or partially fluorinated materials for use as FC membranes is an actual task today, since the use of membranes based on perfluorosulfonate acid has a number of disadvantages limiting their application. The aim of this study is the investigation of sulfonated polyimide (SPI) and materials for use as FC membranes. The relevance of research stems from the fact that the use of the SPI will allow to increase the resistance of the membrane to the constantly changing environment in which PEM operates. The objects of research are sulfonated polyimides. SPIs, especially aromatic SPIs, are attractive to researchers, because of the possibility of obtaining a wide variety of chemical structures and also due to their excellent thermal, mechanical properties and high resistance to aggressive media. The results of this study will be methods of obtaining and evaluating the advantages and disadvantages of SPI-based materials. For the first time, special attention will be paid to advanced development based on SPI with the addition of crown-ether fragments.

Proteins obtained as side-products from starch production (potato and corn proteins) were investigated for wood adhesives application. To improve the wet strength of protein-based adhesives, glyoxal was added as a crosslinking agent. The effect of glyoxal on the wet strength of protein-based adhesives was investigated at different pH, protein: glyoxal ratios and solid content. The alkaline pretreatment of proteins was carried out by two different methods which reduced the molecular weight of proteins to different extents. The effect of molecular weight reduction on the wet strength of protein-glyoxal adhesives was also observed. It was found that pH level affects wet strength more significantly compared to solid content and protein-to-crosslinker ratio. Potato and corn proteins crosslinked with glyoxal showed maximal wet strength results in an acidic pH range