Polarized light emission from polymer emitting diodes (LEDs) is one step towards improved sources of background illumination for efficient liquid crystal displays. It demonstrated that the fabrication organic LEDs based on poly( p ‐phenylene)s by Langmuir–Blodgett technique enables polarization emitted to be controlled. The ratio intensity polarized parallel and perpendicular dipping direction highest reported so far. Photoluminescence electroluminescence spectra are presented discussed.

This article reports on the synthesis, characterization and properties of a series anthracene−containing poly(p-phenylene-ethynylene)-alt-poly(p-phenylene-vinylene)s (PPE−PPV) copolymers with general constitutional unit (Ph−C≡C−Anthr−C≡C−Ph−CH═CH−Ph−CH═CH−)n denoted AnE-PV. Solely linear (AnE-PVaa, -ad, -ae) solely branched (AnE-PVbb) as well mixed (AnE-PVab, -ac, -ba, -cc) alkoxy side chains were grafted to backbone in order tune π−π-stacking ability materials. It has been possible...

An overview of quinoxaline (Qx) based organic semiconducting materials, and their unique building blocks for photovoltaic applications, has been provided.

In the present study, we report a method for preparing fluorescent thermosensitive hybrid material based on monodisperse, poly(N-isopropyl acrylamide) (PNIPAM) microgels covered with CdTe nanocrystals of 3.2 nm diameter. The were covalently immobilized surface PNIPAM microgels. chemical environment around was modified by changing temperature and inducing microgel volume-phase transition. This change provoked steep variation in nanocrystal photoluminescence (PL) intensity such way that when...

Quinoxaline (Qx) has an easily modifiable structure, which allows for fine-tuning its properties through optimizing the length of side chains and kinds aromatic rings in conjugated chains.

Blue light emitting devices based on a rigid‐rod polyelectrolyte–sulfonated poly( p ‐phenylene), see Figure–that has both luminescent and ionic moieties have been prepared their properties investigated. It is reported that the exhibited low onset voltage (3.3 V), external quantum efficiencies reached 0.8%, size of counter ion had pronounced influence electrical characteristics. magnified image

We studied the dark conductivity ${(j}_{\mathrm{dark}}),$ photoconductivity ${(j}_{\mathrm{photo}}),$ and charge carrier photogeneration efficiency \ensuremath{\eta} of poly(N-vinylcarbazole)--based photorefractive (PR) materials with different glass-transition temperatures ${(T}_{g})$ chromophore content $({\ensuremath{\rho}}_{\mathrm{CHR}}).$ Measurements were carried out at wavelengths similar to those used in degenerate four-wave mixing (DFWM) two-beam coupling (2BC) experiments. Both...

The photoinduced anisotropy in polymers and copolymers with a mesogenic nonmesogenic azobenzene moiety the side chain were investigated. results of light-induced optical study thin films obtained by means polarized UV−vis IR absorption spectroscopy are presented. Starting from in-plane optically isotropic samples, irradiation laser at 514 nm induces significant long-term stable anisotropy. build-up has been followed transient experiments time resolution range seconds. coupling alignment...

The electroluminescence and photoluminescence light-emitting devices based on poly(p-phenylene vinylene) (PPV), with emitting layers of different thicknesses, were examined. It was shown that microcavity effects occur in thin PPV single-layer sandwich structures (ITO/PPV/Al, Au/PPV/Al) both electroluminescent photoluminescent emission. Microcavity demonstrated for a range layer thicknesses down to 40 nm. We have successfully prepared resonant-cavity diodes enhanced external quantum...

Structure and composition of titanium nanocluster films were studied on samples prepared by a gas aggregation cluster source based planar magnetron following the Haberland concept. Elemental nanoclusters was X-ray photoelectron spectroscopy (XPS), their crystal structure determined diffraction, optical properties characterized UV–vis spectroscopy. Both as-prepared (without any additional postdeposition treatment) annealed studied. Annealing selected done in air at 420 °C for 1 h followed...

The random distribution of segments linear octyloxy side chains and branched 2-ethylhexyloxy chains, on the backbone anthracene containing poly(p-phenylene-ethynylene)-alt-poly(p-phenylene-vinylene) (PPE-PPV) has resulted in a chain based statistical copolymer, denoted AnE-PVstat, showing optimized features as compared to well defined homologues whose constitutional units are incorporated into its backbone. Electric field independent charge carrier mobility (µhole) for AnE-PVstat was...

Light emitting devices with emission either in the blue, green, and red spectral region have been fabricated based on ladder-type poly(p-phenylene) (LPPP). Color tuning has achieved simply by adjusting LPPP layer thickness. Microcavity effects could be proven to control shape of electroluminescence photoluminescence spectra single between aluminum gold electrodes. The full width at half-maximum was strongly reduced from ∼150 200 nm for ‘‘free space’’ or indium–tin oxide hole injecting...

Two zinc(II)- and two ruthenium(II) containing π-conjugated metallo-polymers were synthesized characterized in detail. We could prove by SEC, analytical ultracentrifugation (AUC) viscosimetry the to be high molar mass materials (M(fs) = 20 000 g · mol(-1) Ru1-2; M(fs) 34 Ru1) exhibiting intrinsic viscosities of up [η] 192 cm(3) g(-1) . Applying spin-coating we produced homogeneous films polymers could, subsequently, investigate photophysical properties solid state. Introducing Ru(II) mixed...

Abstract Novel low‐band gap alternating copolymers consisting of 9,9‐bis(2‐ethylhexyl)fluorene and 4,6‐di(2‐thienyl)thieno[3,4‐ c ][1,2,5]thiadiazole its 3,3″‐dialkyl derivatives were synthesized by Suzuki copolymerization reaction, their photophysical electrochemical properties studied. The possess small optical band 1.3–1.4 eV. absorption covers the whole visible spectral region. long‐wavelength maxima in thin films located at approximately 750–785 nm are significantly red shifted compared...

Ultra-fast and extensive shrinking triggered by both pH and<italic>T</italic>was achieved with monolithic poly(NIPAm-<italic>co</italic>-sodium methacrylate) hydrogels intercalated starch.

Abstract This contribution reports on the synthesis and characterization of thiophene‐ ( P1 , P2 P3 ) anthracene‐ P4 P5) containing PPE‐PPV copolymers. The thermostable, soluble film‐forming polymers were fully characterized by NMR, IR E LEM . A NAL .; they exhibit high molar masses with polydispersity indices below 2.5. position thiophene in polymeric backbone has insignificant influence spectroscopic properties polymers. In contrast, anthracene‐containing reveal dependent optical...

Abstract This article reports on the synthesis, characterization, and properties of various anthracene‐containing poly ( p ‐phenylene‐ethynylene)‐ alt ‐poly( ‐phenylene‐vinylene) (PPE‐PPV) polymers (AnE‐PVs) bearing statistical distributions side chains. Primarily, ratio linear octyloxy branched 2‐ethylhexyloxy chains at poly( ‐phenylene vinylene) (PPV) parts was varied, leading to stat , 1, 2. Furthermore, also containing asymmetric substituted PPV ethynylene) units (bearing methoxy chains)...

Abstract Enormous research effort has been put into optimizing organic-based opto-electronic systems for efficient generation of free charge carriers. This optimization is mainly due to typically high dissociation energy (0.1-1 eV) and short diffusion length (10 nm) excitons in organic materials. Inherently, interplay microscopic structural, chemical, properties plays crucial role. We show that employing combining advanced scanning probe techniques can provide us significant insight the...

New copolymers exhibit interesting electrochromic behaviour with fast response times and they are of interest for optical switching.

Abstract Homopolymers of N ‐(2‐propynyl)carbazole, its copolymers with acetylene, and the homopolymer ‐(2‐propynyl)phenothiazine were prepared using Ti(OBu) 4 /AIEt 3 as catalyst. The carbazole derivative was also by metathetic polymerization catalyzed system WOCl /Ph Sn. both monomers copolymer ‐(2‐propynyl)carbazole a small quantity acetylene are photoconductive.

ABSTRACT New monomers containing 4‐cyanophenyl (–PhCN) groups attached to a thieno[3,2‐ b ]thiophene (TT) or dithieno[3,2‐ :2′,3′‐ d (DTT) structure were synthesized and characterized as 4‐(2,5‐dibromothieno[3,2‐ ]thiophen‐3‐yl)benzonitrile (Br–TT–PhCN) 4,4′‐(2,6‐dibromodithieno[3,2‐ ]thiophene‐3,5‐diyl)dibenzonitrile (Br–DTT–PhCN). The Suzuki coupling of 9,9‐dioctylfluorene‐2,7‐diboronic acid bis(1,3‐propanediol)ester the Br–TT–PhCN Br–DTT–PhCN monomer was utilized for syntheses novel...