engleski

Synthesis and characterization of new aromatic azodioxy and azo polymers

Porous organic architectures have attracted much attention in recent years because of their excellent potential in gas storage and separation, catalysis, optoelectronics and sensing. Molecular building blocks of predefined geometry and functionality can associate through covalent bonds into two-dimensional (2D) and three-dimensional (3D) crystalline or amorphous porous materials. Polymerization property of compounds with multiple nitroso groups could be used for design of azodioxy porous materials. Recently, self- polymerization of tetrakis(arylnitroso)porphyrin and compounds with tetrahedrally oriented nitroso groups resulted with formation of 2D and 3D crystalline organic frameworks (COFs), respectively. In contrast to aromatic polynitroso compounds, systems with azo functional groups form amorphous covalent organic polymers (COPs) which proved to be beneficial for highly selective gas separations. In the present work, we prepared new aromatic trinitroso derivative and studied its polymerization features. In addition, we synthesized new azo-linked polymers by Mills reaction of aromatic trinitroso and diamino derivatives and by the coupling of aromatic trinitro and diamino derivatives. Polymers were characterized using IR spectroscopy, powder X-ray diffraction and thermal methods. Trinitroso compound forms crystalline-like E-azodioxy polymer in solid state, while azo polymers appear as amorphous solids insoluble in common organic solvent and of very high thermal stability. Azodioxy- and azo-linked polymers were also studied by computational methods. Combination of molecular and quantum-mechanical techniques was used to search a conformational space of the simple model compounds to assess the affinity to form 2D networks and to provide some guidelines for the future design of similar systems.

Covalent organic frameworks ; Covalent organic polymers ; Porous materials ; Polynitroso ; Azo ; Azodioxy

nije evidentirano