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Organometallic polyacetylene networks
Šorm, David ; Sedláček, Jan (advisor) ; Balcar, Hynek (referee)
A new type of organometallic polymer networks with a covalent structure of cross-linked substituted polyacetylenes containing Cu2+ or Pd2+ ions (5 to 17 wt%) has been developed. The metal ions were complexed in the networks predominantly with two N-salicylideneaniline ligands covalently bound to two different network monomeric units. Due to the chosen method of complexation, the metal ions have actively participated (as knots of the network) in the formation of cross-linked architecture of the products. For the preparation of organometallic networks two independent methods were used: (i) the direct polymerization of organometallic monomers and (ii) the two-stage method using postpolymerization introduction of metal ions into polyacetylene polymers containing covalently bound N-salicylideneaniline proligands. The starting low-molecular-weight blocks used for the network synthesis were new substances prepared within the framework of the diploma thesis, namely monomers of the mono- and diethynylated N-salicylideneanilines type and diethynylated organometallic monomers in which two molecules of a monoethynylated N-salicylideneaniline complexed one Mt2+ ion. The ethynylated monomers were polymerized to organometallic networks or precursors of these networks via chain-growth coordination polymerization,...
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Heterogeneous Radical Modification of Polypropylene
Brňák, Matúš ; Petruš, Josef (referee) ; Kučera, František (advisor)
The diploma thesis deals with the heterogeneous technique of preparation of grafted polypropylene g maleic anhydride (PP-g-MAH). The knowledge of the course of the reaction and its impact on the PP grafting process are summarized in the theoretical part. The preparation of the grafted PP was carried out in a fluidized polymerization reactor at 115 °C, speed of mixing 210 rpm, reaction time 60 min and pressure 6 bar. The amount of grafted MAH was monitored by using a MAH concentration 3 and 5 wt% and an initiator concentration 0.25; 0.5; 1; and 1.5 wt%. Modification efficiency was compared by using 3 types of PP with different particle morphology and specific surface area. By creating the theoretical model, the maximum surface concentration of MAH was calculated and compared with experimental data. Characterization of PP materials was performed by Electron Scanning Microscopy (SEM), Differential Scanning Calorimetry (DSC) and particle surface analysis by BET. Quantitative analysis of grafted MAH was determined by FTIR spectroscopy and acid-base titration.
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Preparation of functionalized polyacetylene networks by one-step polymerization
Trnková, Kristýna ; Sedláček, Jan (advisor) ; Faukner, Tomáš (referee)
Three new compounds of the aromatic-aliphatic Schiff base type have been prepared via a condensation of 4-ethynylbenzaldehyde with various configurational isomers of 1,2- diaminocyclohexane. The compounds contained two azomethine links and two identical ethynyl groups located at terminal benzene rings. By means of a condensation of 4- ethynylaniline with 5-ethynyl-1,3-benzenedicarbaldehyde an aromatic Schiff base has been prepared which contained two azomethine links interconnecting three benzene rings each of which being substituted with one ethynyl group. All the prepared compounds were used as the monomers of the coordination chain growth polymerization in which the ethynyl groups of the monomers were transformed while the azomethine groups remained preserved. The polymerizations provided polymer networks in which the polyacetylene main chains (formed via polymerization) were extensively interconnected with aromatic-aliphatic or aromatic segments containing azomethine groups. The quantitative conversion of ethynyl groups was achieved in the polymerizations of diethynylated monomers. The polymerization of a triethynylated monomer proceeded under the conversion of the ethynyl groups of the monomer up to 90 %. The triethynylated monomer provided networks with microporous texture manifested by a...
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Preparation of Polyacetylene Networks via Postpolymerization Cross-Linking
Šorm, David ; Sedláček, Jan (advisor) ; Zedník, Jiří (referee)
Using the method of chain growth coordination polymerization, the soluble high molecular weight linear poly(3-ethynylbenzaldehyde) has been prepared, which is the polyacetylene type polymer with reactive benzaldehyde pendant groups. The postpolymerization cross-linking of poly(3-ethynylbenzaldehyde) via a condensation reaction with various aliphatic, aromatic-aliphatic and aromatic diamines has been demonstrated as an efficient tool for the transformation of linear poly(3-ethynylbenzaldehyde) to polymer networks. The cross-linking has been proved to proceed under formation of cross-links of the Schiff base type containing two azomethine groups per one cross-link. In dependence on the cross-linking agent the extent of cross-linking varied from 20 to 100 %. Furthermore, the possibility has been demonstrated to cross-link a soluble linear poly[N-(4-ethynylbenzylidene)-4-terc-butylaniline] via postpolymerization transimination reaction with 1,4-phenylenediamine, again, under formation of cross-links of the Schiff base type containing two azomethine groups per one cross-link. A comparison of the covalent structure and texture of the prepared networks has revealed that the post-polymerization cross-linking using condensation reaction of poly(3-ethynylbenzaldehyde) with diamines can provide polymer...
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Functionalized microporous polymer networks prepared from ethynylarenes
Stahlová, Sabina ; Sedláček, Jan (advisor) ; Etrych, Tomáš (referee) ; Červený, Libor (referee)
The preparation of a new group of functionalized conjugated polymer networks has been described based on spontaneous quaternization polymerization of ethynylpyridines with bis(bromomethyl)arenes. The networks consisted of polyacetylene chains with pyridyl and pyridiniumyl pendants cross-linked with -CH2(arylene)CH2- links. The variation of the ratio of monomer and quaternization agent in the feed modified the ratio of pyridyl and pyridiniumyl groups in the networks (pyridyl/pyridiniumyl ratios from 0 to 1.32). The networks did not exhibit a permanent microporosity that could be confirmed by nitrogen adsorption at 77 K. Nevertheless, all networks were active in capture of CO2 at 293 K (up to 0.73 mmol CO2/g, 750 Torr). It has been hypothesized that CO2 capture reflected formation of a temporary porous texture of the networks through conformational changes of the network segments enabled by the segments mobility at room temperature. The preparation of functionalized conjugated polymer networks with permanent micro/mesoporosity (SBET up to 667 m2 /g) has been described that was based on chain coordination copolymerization of acetylenic monomers. The copolymerization of 1,4-diethynylbenzene or 4,4'-diethynylbiphenyl with mono or diethynylbenzenes bearing NO2 or CH2OH groups has been demonstrated as...
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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...
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Preparation of functionalized polyacetylenes with linear and cross-linked architecture
Havelková, Lucie ; Sedláček, Jan (advisor) ; Balcar, Hynek (referee)
The phenylacetylene type monomers with benzene ring substituted with one or two aldehyde groups (besides an ethynyl group) were efficiently polymerized into linear mostly high-molecular-weight polyacetylenes with aldehyde groups in pendants if the complex [Rh(NBD)acac] was used as the polymerization catalyst. To achieve high yield and molecular weight of the polymer the positioning of the aldehyde group to meta position with respect to the ethynyl group was most appropriate. It was confirmed that polyacetylenes with aldehyde groups were modifiable by a reaction with p-toluidine under formation of Schiff base type pendant groups. 1,3-Diethynylbenzenes with various substituents in position 5 on the ring (R = H, F, Cl, Br, HCO, NO2, COOCH3) were efficiently polymerized with [Rh(NBD)acac] catalyst into microporous or micro/mesoporous polyacetylene networks that exhibited specific surface area from 311 to 1146 m2 /g. In the case of the networks with HC=O groups, the positive effect of these groups was confirmed on the capacity of the network in CO2 and methanol vapor capture. The composition and texture of the networks possessing HC=O groups were partly reversibly modifiable in reaction with p-toluidine.
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Polycyclotrimerization of alkynes with internal ethynyl groups
Sokol, Jiří ; Sedláček, Jan (advisor) ; Balcar, Hynek (referee)
The diynes of both aliphatic and aromatic types comprising either (i) two internal ethynyl groups or (ii) one internal and one terminal ethynyl group in the molecule were revealed as appropriate monomers for the Co2(CO)8 catalyzed polycyclotrimerization yielding high-molecular-weight products. The polycyclotrimerization of aliphatic diynes with a short (CH2)2 link between ethynyl groups and the polycyclotrimerization of aromatic diynes provided polycyclotrimer networks with tri-, tetra-, penta- and hexasubstituted benzene segments. The polycyclotrimers of aliphatic diynes did not exhibit microporous texture. On the other side, the polycyclotrimers of aromatic monomers were mostly microporous with specific surface area up to SBET = 499 m2 /g. The nitrogen desorption isotherms on microporous polycyclotrimers exhibited a significant unclosed hysteresis. This indicated that the penetration of nitrogen into polymers was accompanied by formation of temporary pores or opening permanent pores of worse accessibility.
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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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Functionalized microporous polymer networks prepared from ethynylarenes
Stahlová, Sabina
The preparation of a new group of functionalized conjugated polymer networks has been described based on spontaneous quaternization polymerization of ethynylpyridines with bis(bromomethyl)arenes. The networks consisted of polyacetylene chains with pyridyl and pyridiniumyl pendants cross-linked with -CH2(arylene)CH2- links. The variation of the ratio of monomer and quaternization agent in the feed modified the ratio of pyridyl and pyridiniumyl groups in the networks (pyridyl/pyridiniumyl ratios from 0 to 1.32). The networks did not exhibit a permanent microporosity that could be confirmed by nitrogen adsorption at 77 K. Nevertheless, all networks were active in capture of CO2 at 293 K (up to 0.73 mmol CO2/g, 750 Torr). It has been hypothesized that CO2 capture reflected formation of a temporary porous texture of the networks through conformational changes of the network segments enabled by the segments mobility at room temperature. The preparation of functionalized conjugated polymer networks with permanent micro/mesoporosity (SBET up to 667 m2 /g) has been described that was based on chain coordination copolymerization of acetylenic monomers. The copolymerization of 1,4-diethynylbenzene or 4,4'-diethynylbiphenyl with mono or diethynylbenzenes bearing NO2 or CH2OH groups has been demonstrated as...
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