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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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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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