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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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