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Wybrane kierunki w zakresie modyfikacji poliolefin

Białek Marzena, Bosowska Kornelia, Groch Paweł, Ochędzan-Siodłak Wioletta, Czaja Krystyna

Wiadomości Chemiczne

2024

[Z] 78, 5-6

433--465

Polyolefins, which include various types of polyethylene and polypropylene and, to a much lesser extent, higher polyolefins and olefin copolymers, have been the dominant group of polymersfor years. Thisis due to both the significant development of their production technology, which has become environmentally friendly over the years, and their diverse physicochemical properties. Additionally, the properties of polyolefins, and therefore their areas of application, can be significantly extended by copolymerizaton of olefins with other vinyl compounds, changing their topology and microstructure as well as by modifying their surface or making composite materials. This review reports the state of the art in the field of copolymerization of olefins with alkenylsilsesquioxanes, polar monomers and cycloolefins, which give the resulting materials favorable characteristics in terms of thermal resistance, adhesion and others properties. The next subjects of consideration were the synthesis of multiblock olefin copolymers by chain shuttling polymerization and the synthesis of telechelic polyolefins using, among others, anionic and coordination polymerization. Finally, the modification of polyolefins towards obtaining antibacterial materials and their use in the field of medicine and the packaging industry were discussed.

Vanadium catalysts for ethylene-norbornene copolymerization

Bihun-Kisiel Anna, Ochędzan-Siodłak Wioletta

Polimery

2020

T. 65, nr 11-12

757--770

Cyclic olefin copolymers (COCs) are a promising group of materials with specific, projectable properties. In this group, copolymers of ethylene and norbornene are of particular interest. A variety of transition metal complexes are used for their synthesis, mostly elements from group 4. This review presents the application of vanadium catalysts with various types of ligands in the synthesis of ethylene-norbornene copolymers. The influence of ligands and reaction conditions on the activity of catalyst and selected properties of copolymers are described in this paper.

Kopolimery cyklicznych olefin (COCs) stanowią obiecującą grupę materiałów o specyficznych, możliwych do zaprojektowania właściwościach. Szczególnym zainteresowaniem w tej grupie związków cieszą się kopolimery etylenu z norbornenem. Do ich syntezy stosuje się różnorodne kompleksy metali przejściowych, przede wszystkim pierwiastków z grupy 4. Artykuł stanowi przegląd literatury dotyczącej wykorzystania katalizatorów wanadowych z różnego rodzaju ligandami w syntezie kopolimerów etylenu z norbornenem. Opisano wpływ ligandów i warunków prowadzenia reakcji na aktywność oraz wybrane właściwości otrzymanych kopolimerów.