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Well-defined poly(methyl acrylate) (PMA) and poly(n-butyl acrylate) (PBA) are prepared via photochemically induced atom transfer radical polymerization (photoATRP) using ppm amounts of CuBr2/tris[2-(dimethylamino)ethyl]amine (Me6TREN) catalyst complex without degassing of the polymerization mixture. The effect of light intensity and partial replacement of the excess of expensive Me6TREN ligand with cheaper tertiary amines on kinetics of the polymerization was investigated in various solvents. The addition of triethylamine to photoATRP system resulted in both significant shortening the induction period and increasing the polymerization rate. High livingness of the oxygen tolerant photoATRP system containing triethylamine was proved by chain-extension polymerizations resulting in formation of PMA-b-PBA copolymer. The presented photoATRP system can have tremendous importance from an industrial point of view since the well-defined polyacrylates can be prepared almost without any induction period and in short polymerization time without necessity of both air removal and using the excess of expensive ligand.

Series of alternating conjugated copolymers of thiophene-based monomers substituted with bulky and electron withdrawing 1,2,3-triazole and 1,3,4-oxadiazole pendant groups was synthesized and characterized. Either a Suzuki coupling approach with 1,4-phenylene, 2,5-bis(octyloxy)-1,4-phenylene and 9,9-Dioctylfluorene-2,7-diyl boronates or the Stille reaction with 2,5-thiophenediyl stannane was used for polymer synthesis. The choice of the arylene or thiophene comonomers gives the opportunity to tune solubility, molecular weight and final optical/electrochemical properties of prepared polymers. We achieved improvements of the energetic levels (HOMO, LUMO and band gap). Moreover experiments comparing not only effects of polymer covalent structure but also evaluating the effect of molecular weight distribution on the optical properties using the SEC apparatus equipped by Diode Array Detector (SEC-DAD) and Fluorescence (FLD) detectors were performed.

Homopolymerizations of 2,5-diethynylthiophene into conjugated microporous polymers by (i) chain-growth polymerization and (ii) polycyclotrimerization are described. Both methods provide nearly quantitative yields of thiophene-rich (7.6 mmol thiophene rings/g) networks with specific surface area up to 839 m2/g. The thiophene units enhance the affinity of the networks to CO2 and red-shift the UV/vis and fluorescence absorption and emission bands of the networks, respectively.

The synthesis and photophysical properties of poly{3-[6-(triethylphosphonium)hexyl]-thiophene-2,5-diyl bromide} and poly{3-[6-(triphenylphosphonium)hexyl]-thiophene-2,5-diyl bromide} are reported in the present contribution. Three various polymer precursors (poly[3-(6-bromohexyl)thiophene-2,5-diyl]s) with molecular weights 7.2, 11.8 and 13.2 kg mol−1 respectively and head to tail regioregularity from 62% to 94% were prepared and consecutively transformed into the corresponding polyelectrolytes by a simple quaternization reaction with appropriate phosphines. Synthesized polyelectrolytes exhibited solvatochromism. Detailed aggregation experiments via changing water/DMSO ratio have been performed. Photoluminiscence spectra of the polyelectrolyte solutions indicate that the emission maxima are red-shifted gradually with the increasing solvent polarity. Fluorescence quenching has been studied by interaction with model quenchers: K4[Fe(CN)6] and K3[Fe(CN)6] in water using Stern-Volmer methodology.

We report the synthesis of conjugated highly cross-linked polyacetylene-type networks with a high content of functional groups (–CH2OH, –NO2, –Ph2N, content up to 3.9 mmol/g) via a chain-growth copolymerization of either 1,4-diethynylbenzene or 4,4′-diethynylbiphenyl with functionalized mono- and diethynylbenzenes. The backbone of the networks consists of substituted polyene main chains that are cross-linked by arylene links. The optimized combinations of comonomers in the feed provide functionalized networks with a Brunauer–Emmett–Teller specific surface area up to 667 m2/g and enhanced affinity for CO2 adsorption (compared to the non-functionalized hydrocarbon networks of the same type). The dependence of the specific surface area of the networks on the size and architecture of the comonomers used for the synthesis is discussed in the paper. The reported networks can be classified into the group of conjugated microporous polymers (CMPs). Contrary to the CMPs synthesized by step-growth couplings, significantly lower average comonomer functionality in the feed (f = 1.5–2.0) is sufficient for the high specific surface area to be achieved in the reported polyacetylene-type CMPs.

Conjugated polyelectrolyte with polythiophene main chain and imidazolium side groups, poly{3-[6-(1-methylimidazolium-3-yl) hexyl]thiophene-2,5-diyl bromide}, is investigated. Polymer architecture with hydrophobic main chain and hydrophilic side groups is responsible for the inconvenient behavior of the polymer in solution. Absorption and emission characteristics and supramolecular assembling are investigated by spectroscopic, microscopic and light-scattering methods. We report significant solvatochromism which is observable by a naked eye. Water solutions and mixed solvent systems exhibit most interesting features: supramolecular assembling was investigated by DLS, AFM and TEM techniques and common spectroscopic methods such as UV–vis and fluorescence spectroscopy. Moreover, slow relaxation processes take part in water as it is evidenced by time evolution of absorption spectra. It is a result of vanishing of inter- and intramolecular interactions. These interactions are responsible for extraordinary solution behavior of the ionic polythiophene.

The long-term stability of poly{[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene]vinylene} (MEH-PPV) in solutions exposed to air at daylight and in the dark at room temperature has been studied using the size exclusion chromatography (SEC), UV/vis, fluorescence and IR spectra of aged samples, and comparison of UV/vis spectra of SEC fractions. Solvents currently used in the preparation, analysis and processing of MEH-PPV were used: tetrahydrofuran (THF), chloroform (CHCl3) and chlorobenzene (PhCl). The SEC-DAD data revealed a serious decrease in the delocalization of electrons in MEH-PPV chains, even in the large ones, which proves a deep damage to the structure of the chains prior to their cleavage. The IR spectra of aged samples show that the saturation of main-chain double bonds and the changes in the substitution of phenylene rings are the main chemical structure defects present in chains of aged MEH-PPV. The rate as well as the extent of the overall degradation process is ca ten to fifty times enhanced by the ordinary daylight. The rate of cleavage and the damage to the structure of MEH-PPV molecules are significantly influenced by the choice of the solvent; they increase in the order: PhCl < CHCl3 < THF. PhCl can be recommended as one of the best solvents for MEH-PPV processing from solutions.

Aqueous solutions of poly(thiophen-3-ylacetic acid) neutralized with LiOH, NaOH, and CsOH were for the first time investigated using conductivity measurements (in concentrations, c, ranging from 2·10− 5 to 8·10− 2 mol/dm3 and temperatures from 278.15 to 313.15 K), transport number measurements (at 298.15 K) and osmotic coefficient measurements using vapor pressure osmometry (at 313.15 K) and cryoscopy, in order to identify essential electrochemical characteristics of this conjugated polyelectrolyte. The measurements of the polyion constituent transport number data suggested that a fraction of counterions traveled associated with polyions. The fraction of “free” counterions, determined from the transport measurements by the association theory of Huizenga, Grieger, and Wall was around 0.5, which is in good agreement with the osmotic coefficient data. Neither the fraction of “free” counterions, nor the osmotic coefficient significantly depends on the nature of the counterion species. The results obtained were analyzed in terms of the Poisson–Boltzmann theory, Manning's condensation approach, and modern scaling theory. Good agreement between the theoretical results and the fraction of “free” counterions, determined from the combination of the transport number and conductivity measurements, was obtained. The osmotic coefficients were well reproduced by the Poisson–Boltzmann cell model theory.

Series of high-cis and cis/trans poly[(fluorophenyl)acetylene]s (PFPhA) have been prepared by polymerization of (2-fluorophenyl)acetylene, (3-fluorophenyl)acetylene, and (4-fluorophenyl)acetylene with catalysts: [Rh(1,5-cyclooctadiene) OCH3]2 (high-cis PFPhAs) and tungsten(VI) oxychloride/tetraphenyltin (cis/trans PFPhAs). The molecular weight and configurational stability under various conditions at room temperature were studied for both PFPhAs series by means of size exclusion chromatography, 1H-NMR, and UV-vis techniques. All samples exhibited slow degradation when exposed to the atmosphere in the solid state; the rate of degradation was independent on the F-position on the Ph ring. The rate of degradation increased up to three orders of magnitude in the tetrahydrofuran solution where it was higher for high-cis polymers compared with their cis/trans counterparts. The degradation of high-cis PFPhAs was accompanied by significant cis-to-trans isomerization in aerated tetrahydrofuran solution. Rate of degradation and isomerization exhibited the same dependence on the F-position on the Ph ring. The hypothesis was postulated that the degradation of high-cis PFPhAs in solution was accelerated by cis-to-trans isomerization due to which the content of unpaired electrons on the main chains is enhanced. In both high-cis and cis/trans series of polymers the ortho-substituted isomers exhibited an enhanced stability compared with meta- and para-substituted isomers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4296–4309, 2010

A series of fluorene-based copolymers containing hole blocking/electron transporting diphenyloxadiazole units were synthesized by means of Suzuki-Miyaura coupling of selected aromatic dibromo- and diboronato- derivatives catalyzed with a Pd(PPh3)4 catalyst. All of the copolymers with various composition of main-chain units were characterized by SEC chromatography, NMR, UV–vis, fluorescence and IR spectroscopy, and DSC. The emission stability of fluorene copolymers was improved by the replacement of alkyl groups on the C-9 carbon of fluorene with aryl groups or by the incorporation of anthracene units into the copolymer main chain. A comparison of luminescence properties of pristine and annealed thin layers of studied copolymers was performed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4532–4546, 2009