National Repository of Grey Literature 9 records found  Search took 0.01 seconds. 
Functionalized hyper-cross-linked porous polyacetylenes
Havelková, Lucie
An atom-economic one-step chain-growth coordination homopolymerization providing high yields of functionalized hyper-cross-linked polyacetylenes with permanent micro/mesoporous texture and specific surface area up to 1062 m2 /g was introduced and optimized. Substituted 1,3-diethynylbenzenes served as monomers simultaneously providing functionalization and hyper-cross-linking of the networks. The homopolymerization was compatible with the heteroatom groups of the monomers and allowed to prepare polyacetylene networks with the wide spectrum of univalent functional groups: -F, -Cl, -Br, -NO2, -COOCH3, -CH2OH, -COOH and -CH=O decorating the aromatic segments of the networks in a high extent (7.87 mmol/g). A novel two-step synthesis of functionalized hyper-cross-linked polyacetylenes was introduced combining chain-growth coordination polymerization of acetylenic monomers and covalent templating using acetal and Schiff base protecting groups. By postpolymerization hydrolytic removal of the protecting segments from the primary networks, the networks with a high content (up to 9.61 mmol/g) of univalent functional groups -CH2OH, -CH=O and -NH2 were prepared. These groups were placed either on the cross-linking or linear (aromatic and aliphatic) network segments, even in the vicinity of the main...
Functionalized hyper-cross-linked porous polyacetylenes
Havelková, Lucie ; Sedláček, Jan (advisor) ; Brožek, Jiří (referee) ; Balcar, Hynek (referee)
An atom-economic one-step chain-growth coordination homopolymerization providing high yields of functionalized hyper-cross-linked polyacetylenes with permanent micro/mesoporous texture and specific surface area up to 1062 m2 /g was introduced and optimized. Substituted 1,3-diethynylbenzenes served as monomers simultaneously providing functionalization and hyper-cross-linking of the networks. The homopolymerization was compatible with the heteroatom groups of the monomers and allowed to prepare polyacetylene networks with the wide spectrum of univalent functional groups: -F, -Cl, -Br, -NO2, -COOCH3, -CH2OH, -COOH and -CH=O decorating the aromatic segments of the networks in a high extent (7.87 mmol/g). A novel two-step synthesis of functionalized hyper-cross-linked polyacetylenes was introduced combining chain-growth coordination polymerization of acetylenic monomers and covalent templating using acetal and Schiff base protecting groups. By postpolymerization hydrolytic removal of the protecting segments from the primary networks, the networks with a high content (up to 9.61 mmol/g) of univalent functional groups -CH2OH, -CH=O and -NH2 were prepared. These groups were placed either on the cross-linking or linear (aromatic and aliphatic) network segments, even in the vicinity of the main...
Porous polymer networks prepared from ethynylpyridines
Titlová, Štěpánka ; Sedláček, Jan (advisor) ; Sedláček, Ondřej (referee)
Series of new micro/mesoporous polymer networks with high content of pyridine segments was prepared. For the preparation were used ethynylpyridine type of monomers which were successfully homopolymerized and copolymerized with hydrocarbon diethynylarenes by chain-growth coordination polymerization catalyzed with [Rh(NBD)acac] complex. Polymerizations provided polyacetylene networks with main chains densely cross- linked by pyridine or arylene links. Prepared pyridine networks showed specific surface area SBET from 308 m2 /g to 923 m2 /g and variable content of pyridine segments in an interval from 3,27 mmol/g to 7,86 mmol/g. In networks, pyridine segments made part of interchain links or side groups. Networks with pyridine segments were successfully quaternized by heterogeneous postpolymerization reaction with bromoethane to form well covalently defined networks containing N-ethylpyridinium segments. Quaternized networks containing pyridinim segments in amount from 2,41 mmol/g to 4,24 mmol/g had preserved micro/mesoporous texture with values of SBET from 331 m2 /g to 592 m2 /g. Polyacetylene networks with N-ethylpyridinium segments were prepared also by catalyst-free (spontaneous) quaternization polymerization of diethylpyridines. These networks were worse covalently defined and had proved lower...
Conjugated porous polymers derived from diethynylarenes by chain-growth polymerization and polycyclotrimerization
Slováková, Eva ; Sedláček, Jan (advisor) ; Merna, Jan (referee) ; Červený, Libor (referee)
4 ABSTRACT The synthesis has been described yielding a new type of rigid conjugated polymer networks which possess a high content of permanent micropores and macropores and exhibit high surface areas up to 1469 m2/g. The networks have been prepared via chain-growth coordination polymerization catalysed with insertion catalysts based on Rh complexes. This polymerization has been newly applied to bifunctional acetylenic monomers of diethynylarene type (1,4-diethynylbenzene, 1,3-diethynylbenzene and 4,4'-diethynylbiphenyl). The covalent structure of the networks consists of the polyacetylene main chains densely connected by arylene struts. The W and Mo metathesis catalysts have been revealed as inefficient for the synthesis of these networks. The increase in the polymerization temperature and time has been shown to affect positively the content and the diameter (up to 22 nm) of the mesopores in the networks. A mechanism has been proposed that explains the mesopores formation as a result of mutual knitting of small particles of the microporous polymer. The application of emulsion polymerization technique allowed to prepare texturally hierarchical polyacetylene networks possessing interconnected open macropores (diameter up to 4,8 μm) the walls of which exhibited micro/mesoporous texture. It was demonstrated...
Conjugated porous polymers derived from diethynylarenes by chain-growth polymerization and polycyclotrimerization
Slováková, Eva
The synthesis has been described yielding a new type of rigid conjugated polymer networks which possess a high content of permanent micropores and macropores and exhibit high surface areas up to 1469 m2/g. The networks have been prepared via chain-growth coordination polymerization catalysed with insertion catalysts based on Rh complexes. This polymerization has been newly applied to bifunctional acetylenic monomers of diethynylarene type (1,4-diethynylbenzene, 1,3-diethynylbenzene and 4,4'-diethynylbiphenyl). The covalent structure of the networks consists of the polyacetylene main chains densely connected by arylene struts. The W and Mo metathesis catalysts have been revealed as inefficient for the synthesis of these networks. The increase in the polymerization temperature and time has been shown to affect positively the content and the diameter (up to 22 nm) of the mesopores in the networks. A mechanism has been proposed that explains the mesopores formation as a result of mutual knitting of small particles of the microporous polymer. The application of emulsion polymerization technique allowed to prepare texturally hierarchical polyacetylene networks possessing interconnected open macropores (diameter up to 4,8 μm) the walls of which exhibited micro/mesoporous texture. It was demonstrated that...
Porous polymer networks prepared from ethynylpyridines
Titlová, Štěpánka ; Sedláček, Jan (advisor) ; Sedláček, Ondřej (referee)
Series of new micro/mesoporous polymer networks with high content of pyridine segments was prepared. For the preparation were used ethynylpyridine type of monomers which were successfully homopolymerized and copolymerized with hydrocarbon diethynylarenes by chain-growth coordination polymerization catalyzed with [Rh(NBD)acac] complex. Polymerizations provided polyacetylene networks with main chains densely cross- linked by pyridine or arylene links. Prepared pyridine networks showed specific surface area SBET from 308 m2 /g to 923 m2 /g and variable content of pyridine segments in an interval from 3,27 mmol/g to 7,86 mmol/g. In networks, pyridine segments made part of interchain links or side groups. Networks with pyridine segments were successfully quaternized by heterogeneous postpolymerization reaction with bromoethane to form well covalently defined networks containing N-ethylpyridinium segments. Quaternized networks containing pyridinim segments in amount from 2,41 mmol/g to 4,24 mmol/g had preserved micro/mesoporous texture with values of SBET from 331 m2 /g to 592 m2 /g. Polyacetylene networks with N-ethylpyridinium segments were prepared also by catalyst-free (spontaneous) quaternization polymerization of diethylpyridines. These networks were worse covalently defined and had proved lower...
Conjugated porous polymers derived from diethynylarenes by chain-growth polymerization and polycyclotrimerization
Slováková, Eva ; Sedláček, Jan (advisor) ; Merna, Jan (referee) ; Červený, Libor (referee)
4 ABSTRACT The synthesis has been described yielding a new type of rigid conjugated polymer networks which possess a high content of permanent micropores and macropores and exhibit high surface areas up to 1469 m2/g. The networks have been prepared via chain-growth coordination polymerization catalysed with insertion catalysts based on Rh complexes. This polymerization has been newly applied to bifunctional acetylenic monomers of diethynylarene type (1,4-diethynylbenzene, 1,3-diethynylbenzene and 4,4'-diethynylbiphenyl). The covalent structure of the networks consists of the polyacetylene main chains densely connected by arylene struts. The W and Mo metathesis catalysts have been revealed as inefficient for the synthesis of these networks. The increase in the polymerization temperature and time has been shown to affect positively the content and the diameter (up to 22 nm) of the mesopores in the networks. A mechanism has been proposed that explains the mesopores formation as a result of mutual knitting of small particles of the microporous polymer. The application of emulsion polymerization technique allowed to prepare texturally hierarchical polyacetylene networks possessing interconnected open macropores (diameter up to 4,8 μm) the walls of which exhibited micro/mesoporous texture. It was demonstrated...
Synthesis of microporous polymer networks with azomethine links
Hašková, Alena ; Sedláček, Jan (advisor) ; Balcar, Hynek (referee)
A series of following Schiff base type monomers with two terminal ethynyl groups and one or two azomethine groups have been synthesized: N-(4-ethynylbenzylidene)(4-ethynylaniline), positional isomers of N,N'-(1,4-phenylene)bis(1-(ethynylphenyl)methanimine) and positional isomers of 1,1'-(1,4-phenylene)bis[(N-ethynylphenyl)methanimine]. These monomers have been successfully polymerized in chain-growth mode with the use of [Rh(NBD)acac] as the coordination catalyst into densely cross-linked polyacetylene networks with micro/mesoporous texture and specific surface in hundreds of m2 /g. The positive correlation between the conversion of ethynyl groups and specific surface area on one hand and the increase in reaction temperature and reaction time on the other side was proven. Varying the composition and architecture of polymerized monomers affected particularly the distribution of micropores and mesopores in the networks. The postpolymerization modification of poly[N-(4-ethynylbenzylidene)(4- ethynylaniline)] network has been performed consisting in a partial releasing the links connecting the linear segments of the network. It was confirmed that despite this modification the network preserved the micro/mesoporous texture.
Conjugated porous polymers derived from diethynylarenes by chain-growth polymerization and polycyclotrimerization
Slováková, Eva
The synthesis has been described yielding a new type of rigid conjugated polymer networks which possess a high content of permanent micropores and macropores and exhibit high surface areas up to 1469 m2/g. The networks have been prepared via chain-growth coordination polymerization catalysed with insertion catalysts based on Rh complexes. This polymerization has been newly applied to bifunctional acetylenic monomers of diethynylarene type (1,4-diethynylbenzene, 1,3-diethynylbenzene and 4,4'-diethynylbiphenyl). The covalent structure of the networks consists of the polyacetylene main chains densely connected by arylene struts. The W and Mo metathesis catalysts have been revealed as inefficient for the synthesis of these networks. The increase in the polymerization temperature and time has been shown to affect positively the content and the diameter (up to 22 nm) of the mesopores in the networks. A mechanism has been proposed that explains the mesopores formation as a result of mutual knitting of small particles of the microporous polymer. The application of emulsion polymerization technique allowed to prepare texturally hierarchical polyacetylene networks possessing interconnected open macropores (diameter up to 4,8 μm) the walls of which exhibited micro/mesoporous texture. It was demonstrated that...

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