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Study of molecular weight and configurational stability of substituted polyacetylenes
Trhlíková, Olga
Complexes [Rh(cycloolefin)(acac)] (cycloolefin = norborna-2,5-diene, cycloocta- 1,5-diene and cyclooctatetraene) were investigated as catalysts of polymerization of monosubstituted acetylenes into stereoregular cis-transoid polyacetylenes. All complexes were highly active in arylacetylenes polymerizations in both coordinating and non-coordinating solvents. Selection of solvent and cycloolefin ligand of the catalyst allowed the control over polymer MW. The onset of initiation in the [Rh(cycloolefin)(acac)]/monomer systems proceeded as the proton transfer from the monomer molecule to the acac ligand under the release of acetylacetone and coordination of -C≡CR ligand to Rh(cycloolefin) moiety. Cis-transoid poly(phenylacetylene) and poly[(2,4-difluorophenyl)acetylene]s with required initial MW were prepared with these catalysts and submitted to the long-term ageing in which the polymers were exposed to the atmosphere and diffuse daylight either dissolved in tetrahydrofuran or in the solid state. Tightly connected processes of cis-to-trans isomerization of the polymer main-chains double bonds and oxidative degradation were found to proceed during polymers ageing in the solution. Besides, the formation of corresponding cyclotrimers accompanied the polymers ageing. However, the cyclotrimers amount was too...
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Ionic polyacetylene type polymers and polymer networks by catalyst-free quaternization polymerization
Faukner, Tomáš
(Doctoral Thesis, 2016, Mgr. Tomáš Faukner, IONIC POLYACETYLENE TYPE POLYMERS AND POLYMER NETWORKS BY CATALYST FREE QUATERNIZATION POLYMERIZATION) The composition and structure of a series of ionic π-conjugated poly(monosubstituted acetylene)s prepared via catalyst-free quaternization polymerization (QP) of 2-ethynylpyridine (2EP) activated with equimolar amount of alkyl halide [RX = ethyl bromide, ethyl iodide, nonyl bromide and haxadecyl (cetyl) bromide] as a quaternizing agent (QA) have been studied in detail. The performed QPs gave ionic polymers well soluble in polar solvents, with approximately half of pyridine rings quaternized, which implies that also non-quaternized monomers were involved in the process of QP. The configurational structure of polyacetylene main chains was suggested based on 1 H NMR, IR as well as Raman (SERS) spectral methods. The QPs in bulk gave more expected irregular cis/trans polymers while the QPs in acetonitrile solution gave high-cis polymers. A series of prepared symmetrical bi-pyridylacetylene based monomers has been polymerized via QP approach resulting into a series of new ionic π-conjugated poly(disubstituted acetylene) type materials. It is therefore obvious that the mechanism of quaternization activation frequently applied on monosubstituted...
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Preparation of polyacetylenes with N-benzylidene-2-hydroxyaniline groups
Zhernakova, Yulia ; Sedláček, Jan (advisor) ; Vyskočilová, Eliška (referee)
The following monoethynylated N-benzylidene-2-hydroxyanilines were prepared: N-(4- ethynylbenzylidene)-2-hydroxyaniline, N-(3-ethynylbenzylidene)-2-hydroxyaniline, N-(4- ethynylbenzylidene)-2-hydroxy-5-nitroaniline and N-(3-ethynylbenzylidene)-2-hydroxy-5- nitroaniline, which differed in the position of the ethynyl group on the benzylidene ring and the substitution of the hydroxyaniline ring. Monoethynylated N-benzylidene-2- hydroxyanilines were used as the monomers for the chain-growth coordination homo- and copolymerization. The homopolymerization resulted in linear polyacetylene homopolymers with N-benzylidene-2-hydroxyaniline substituents. The copolymerization with multiethynylarene-type cross-linkers provided densely cross-linked copolymeric polyacetylene networks. The linear units of the networks carried N-benzylidene-2- hydroxyaniline substituents, the interconnection between the chains of the networks being realized by arene links. The texture parameters of the prepared networks significantly depended on the type of comonomers used. The highest specific surface area values (~530 m2 /g) were achieved with networks prepared by copolymerization of N-(4- ethynylbenzylidene)-2-hydroxyaniline or N-(3-ethynylbenzylidene)-2-hydroxyaniline,with 4,4'-diethynylbiphenyl used as a cross-linker. Selected...
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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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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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Substituted polyacetylenes with aldehydic groups: preparation and postpolymerization modification
Zhernakova, Yulia ; Sedláček, Jan (advisor) ; Faukner, Tomáš (referee)
Homopolymerization of 3-ethynylbenzaldehyde, 4-ethynylbenzaldehyde and 1- ethynylbenzene-3,5-dicarbaldehyde and copolymerization of these monomers with phenylacetylene have been studied with the aim to prepare soluble homo and copolymers of polyacetylene type with aldehyde groups in pendants. The Rh(I) complexes have been demonstrated to be efficient catalysts of these polymerizations. The solubility of homopolymers prepared was controlled by the symmetry/non-symmetry of the substitution of pendant phenyl groups of the monomeric units. Non-symmetrically substituted 3-ethynylbenzaldehyde provided soluble homopolymer, on the other hand symmetrically substituted 4-ethynylbenzaldehyde and 1- ethynylbenzene-3,5-dicarbaldehyde gave insoluble homopolymers: the insolubility of these homopolymers most probably reflected a tight packing of symmetrically substituted polymer chains in the solid phase. 3-Ethynylbenzaldehyde, 4-ethynylbenzaldehyde and 1-ethynylbenzene- 3,5-dicarbaldehyde when copolymerized with phenylacetylene yielded soluble binary copolymers with a tuneable composition. The polymerizability of 3-ethynylbenzaldehyde and 1- ethynylbenzene-3,5-dicarbaldehyde was close to that of phenylacetylene. However, 4- ethynylbenzaldehyde exhibited about half the polymerizability than phenylacetylene....
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Ionic polyacetylene type polymers and polymer networks by catalyst-free quaternization polymerization
Faukner, Tomáš
(Doctoral Thesis, 2016, Mgr. Tomáš Faukner, IONIC POLYACETYLENE TYPE POLYMERS AND POLYMER NETWORKS BY CATALYST FREE QUATERNIZATION POLYMERIZATION) The composition and structure of a series of ionic π-conjugated poly(monosubstituted acetylene)s prepared via catalyst-free quaternization polymerization (QP) of 2-ethynylpyridine (2EP) activated with equimolar amount of alkyl halide [RX = ethyl bromide, ethyl iodide, nonyl bromide and haxadecyl (cetyl) bromide] as a quaternizing agent (QA) have been studied in detail. The performed QPs gave ionic polymers well soluble in polar solvents, with approximately half of pyridine rings quaternized, which implies that also non-quaternized monomers were involved in the process of QP. The configurational structure of polyacetylene main chains was suggested based on 1 H NMR, IR as well as Raman (SERS) spectral methods. The QPs in bulk gave more expected irregular cis/trans polymers while the QPs in acetonitrile solution gave high-cis polymers. A series of prepared symmetrical bi-pyridylacetylene based monomers has been polymerized via QP approach resulting into a series of new ionic π-conjugated poly(disubstituted acetylene) type materials. It is therefore obvious that the mechanism of quaternization activation frequently applied on monosubstituted...
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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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Ionic polyacetylene type polymers and polymer networks by catalyst-free quaternization polymerization
Faukner, Tomáš ; Zedník, Jiří (advisor) ; Balcar, Hynek (referee) ; Sedlařík, Vladimír (referee)
(Doctoral Thesis, 2016, Mgr. Tomáš Faukner, IONIC POLYACETYLENE TYPE POLYMERS AND POLYMER NETWORKS BY CATALYST FREE QUATERNIZATION POLYMERIZATION) The composition and structure of a series of ionic π-conjugated poly(monosubstituted acetylene)s prepared via catalyst-free quaternization polymerization (QP) of 2-ethynylpyridine (2EP) activated with equimolar amount of alkyl halide [RX = ethyl bromide, ethyl iodide, nonyl bromide and haxadecyl (cetyl) bromide] as a quaternizing agent (QA) have been studied in detail. The performed QPs gave ionic polymers well soluble in polar solvents, with approximately half of pyridine rings quaternized, which implies that also non-quaternized monomers were involved in the process of QP. The configurational structure of polyacetylene main chains was suggested based on 1 H NMR, IR as well as Raman (SERS) spectral methods. The QPs in bulk gave more expected irregular cis/trans polymers while the QPs in acetonitrile solution gave high-cis polymers. A series of prepared symmetrical bi-pyridylacetylene based monomers has been polymerized via QP approach resulting into a series of new ionic π-conjugated poly(disubstituted acetylene) type materials. It is therefore obvious that the mechanism of quaternization activation frequently applied on monosubstituted...
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