We present the synthesis of a new amphiphilic poly(3-hexylthiophene)-block-poly(tetrabutylammonium-4-styrenesulfonate) (P3HT-b-PSS–/TBA+) block copolymer via polymer–polymer click reaction. The ...P3HT-alkyne block has a molecular weight of 17.6 kg/mol (SEC)/11.3 kg/mol (MALDI-ToF), and the block copolymer has a high purity due to the complete removal of both precursor blocks by a column chromatographic approach. The fluorinated styrenesulfonate polymer P(SS-CH2-CF3)-N3 is synthesized by reversible addition–fragmentation transfer (RAFT) polymerization, and a specific RAFT agent is used to avoid labile ester linkages. SEC with THF as solvent overestimates the molecular weight (MW) of P(SS-CH2-CF3)-N3, but 1H NMR spectroscopy allows for the exact calculation of the molecular weight. We show that the precursor block copolymer P3HT-b-P(SS-CH2-CF3) forms wormlike micelles by self-assembly with a crystalline P3HT core (diameter <30 nm) in polar solvents. In these BCP micelles the P(SS-CH2-CF3) precursor in the corona can be deprotected, and P3HT-b-PSS–/TBA+ micelles are formed. Additionally, the compartmentalized in situ synthesis of highly crystalline TiO2 (anatase) nanocrystals (<10 nm) stabilized within the PSS corona of the micelles is demonstrated. The resulting P3HT–TiO2 nanocomposites with well-defined nanoscale morphology are water-processable, and they are investigated in detail by cryo-TEM and UV–vis spectroscopy.
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IJS, KILJ, NUK, PNG, UL, UM
Die Authentizitätsprüfungen von Lebensmitteln und deren Rohstoffen ist in der amtlichen Lebensmittelüberwachung schon seit einiger Zeit ein großes Themenfeld – es geht um die Aspekte ...Lebensmitteltäuschung und Lebensmittelsicherheit. Eine effiziente und kostengünstige Untersuchungsmethode stellt das DNA‐basierte Next Generation Sequencing (NGS) dar, hier speziell das Metabarcoding. Hierbei wird eine Hochdurchsatzsequenzierung mittels short‐read sequencing (Illumina MiSeq) durchgeführt.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
"Daily Production" beschäftigt sich am Beispiel traditioneller Bekleidung mit dem Verhältnis von Tradition und Erneuerung, kulturellen Eigenheiten und globalen Ökonomien. Wie steht es heute um ...spezifische kulturelle Traditionen oder Phänomene, wie kommen sie zustande, was bedeuten sie, wie verändern sie sich? Beleuchtet wird der Zusammenhang von Tradition, Produktion und Arbeit im Hinblick auf die Gestaltung, Herstellung und Nutzung von Textilem.
We report measurements of the dispersion in the linear optical properties (linear absorption coefficient and refractive index) of polydiacetylene
para-toluene sulfonate (PDA–PTS) single crystal ...waveguide films prepared by thermal polymerization of the monomer free floating in solution and subsequent attachment of the film to the substrate. A maximum absorption coefficient >10
5
cm
−1
at a wavelength of 620 nm is measured for polarization parallel to the polymer chains, in agreement with previous measurements. The refractive index parallel to the polymer axis is significantly lower in these thin films as compared to bulk PDA–PTS crystals, whereas the index perpendicular to the chains is comparable to that of bulk crystals. Sellmeier parameters describing the dispersion of the refractive index in the near-infrared spectral range are given.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
