ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTModification of polymer properties through ion incorporationC. Geraldine Bazuin and Adi EisenbergCite this: Ind. Eng. Chem. Prod. Res. Dev. 1981, 20, 2, 271–286Publication Date (Print):June 1, 1981Publication History Published online1 May 2002Published inissue 1 June 1981https://pubs.acs.org/doi/10.1021/i300002a010https://doi.org/10.1021/i300002a010research-articleACS PublicationsRequest reuse permissionsArticle Views395Altmetric-Citations133LEARN...

Dense arrays of well-dispersed gold nanoparticles (AuNPs) on optical fibers are shown to bridge the gap in sensitivity and sensing performance between localized surface plasmon resonance (LSPR) classical SPR sensing. A simple self-assembly method relying a poly(styrene- b-4-vinylpyridine) (PS- b-P4VP) block copolymer brush layer was used immobilize AuNPs different diameters from 10 92 nm fibers. In comparison with standard AuNP deposition methods using (3-aminopropyl)trimethoxysilane (APTMS)...

Recent progress in photoresponsive polymers based on three common supramolecular design strategies, namely ionic, hydrogen and halogen bonding, is reviewed.

We describe surface-enhanced Raman spectroscopy (SERS) aptasensors that can indirectly detect MC-LR and MC-RR, individually or simultaneously, in natural water algal culture. The sensor is constructed from nanoparticles composed of successive layers Au core–SERS label–silver shell–gold shell (Au@label@Ag@Au NPs), functionalized on the outer surface by and/or MC-RR aptamers. These NPs are immobilized asymmetric nanoflowers (AuNFs) dispersed planar silicon substrates through DNA hybridization...

We demonstrate experimentally for the first time that illumination of azobenzene derivatives leads to changes in molecular environment similar those observed on heating but are highly heterogeneous at submolecular scale. This localized photoplasticization, which can be associated with a free volume gradient, helps understand puzzling phenomenon photoinduced macroscopic material flow and photoexpansion upon far below glass transition temperature (T(g)). The findings stem from correlation...

The development of plasmonic-active nanosensors for surface-enhanced Raman scattering (SERS) sensing is important gaining knowledge on intracellular and extracellular chemical processes, hypoxia detection, label-free detection neurotransmitters metabolites, among other applications in cell biology. fabrication SERS optophysiology measurements using substrates such as nanofibers with a uniform distribution plasmonic nanoparticles (NPs) remains critical hurdle. We report here strategy block...

Mercury(II) ions (Hg2+) and silver (Ag+) are two of the most hazardous pollutants causing serious damage to human health. Here, we constructed surface-enhanced Raman scattering (SERS)-active nanofibers covered with 4-mercaptopyridine (4-Mpy)-modified gold nanoparticles detect Hg2+ Ag+. Experimental evidence suggests that observed spectral changes originate from combined effect (i) coordination between nitrogen on 4-Mpy metal (ii) molecular orientation (from flatter more perpendicular respect...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTNovel liquid-crystalline polymeric materials via noncovalent "grafting"C. Geraldine Bazuin and Frank A. BrandysCite this: Chem. Mater. 1992, 4, 5, 970–972Publication Date (Print):September 1, 1992Publication History Published online1 May 2002Published inissue 1 September 1992https://pubs.acs.org/doi/10.1021/cm00023a005https://doi.org/10.1021/cm00023a005research-articleACS PublicationsRequest reuse permissionsArticle...

We demonstrate complete all-optical erasure of high-modulation-depth azopolymer surface patterns at ambient conditions. Applying selective optical and rewriting can be translated into complex with spatially varying grating vector directions.

A nanothin block copolymer (BCP) brush-layer film adsorbed on glass nanofibers is shown to address the long-standing challenge of forming a template for deposition dense and well-dispersed nanoparticles highly curved surfaces, allowing development an improved nanosensor neurotransmitters. We employed polystyrene- block-poly(4-vinylpyridine) BCP plasmonic gold (AuNPs) 52 nm in diameter fabrication pulled fibers with diameters down 200 nm. The method simple, using only solution processes...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGeneration of Liquid Crystalline Polymeric Materials from Non Components via Ionic ComplexationC. Geraldine Bazuin and Amir TorkCite this: Macromolecules 1995, 28, 26, 8877–8880Publication Date (Print):December 1, 1995Publication History Published online1 May 2002Published inissue 1 December 1995https://pubs.acs.org/doi/10.1021/ma00130a027https://doi.org/10.1021/ma00130a027research-articleACS PublicationsRequest reuse permissionsArticle...

Thin films of poly(styrene-b-4-vinylpyridine) (PS4VP) [Mn(PS) = 71.9 kg/mol; Mn(P4VP) 30.2 kg/mol] mixed with 1,5-dihydroxynaphthalene (DHN) were dip-coated onto flat substrates from THF solutions. The resultant nanostructures characterized by AFM, TEM, infrared spectroscopy, contact angle measurements, and cyclic voltammetry. DHN selectively enriches the P4VP domains through hydrogen bond complexation, giving relative block compositions that should result in lamellar morphology bulk....

A series of spacer-free ionic azobenzene-containing stoichiometric complexes was prepared from monosulfonated azo dyes and cationic polyelectrolytes [methylated poly(4-vinylpyridine) (PVP) poly(dimethylaminoethyl methacrylate) (PDM)]. Their thermal structural characteristics optical responses, particularly photoinduced birefringence (PIB) surface relief grating (SRG) inscription, were investigated as a function selected molecular parameters. All the have high apparent Tg values, 180−210 °C,...

We created novel nonphospholipid photosensitive liposomes from a mixture of monoacylated azobenzene amphiphile (AzoC10N+) and cholesterol sulfate (Schol). This system belongs to the family sterol-enriched that were shown form stable large unilamellar vesicles (LUVs) with enhanced impermeability. Fluid bilayers successfully prepared AzoC10N+/Schol (25/75 molar ratio) mixtures, LUVs could be derived at room temperature using standard extrusion methods. The isomerization process...

This contribution offers a comprehensive understanding of the factors that govern morphologies Langmuir-Blodgett (LB) monolayers amphiphilic diblock copolymers (BCs). is achieved by detailed investigation wide range polystyrene-poly(4-vinyl pyridine) (PS-P4VP) block copolymers, in contrast to much more limited ranges previous studies. Parameters are varied include ratios (mainly for similar total molecular weights, occasionally other weights), presence or not 3-n-pentadecylphenol (PDP,...

Recent literature has shown that the thickness of dip-coated films a V-shaped dependence on dip-coating rate when very slow rates are included. For supramolecular block copolymer films, small molecule (SM) uptake and film morphology also rate-dependent, as previously for poly(styrene-b-4-vinylpyridine) (PS–P4VP) in THF solutions containing naphthol (NOH) naphthoic acid (NCOOH). Here, these investigations extended to p-dioxane, toluene, CHCl3 solutions. The is validated each solvent, but with...

The electrospinning of continuous fibers normally requires the presence a network topological entanglements in solution, limiting spinnability low molecular weight polymers. Here, we show that supramolecular approach can improve, and even render possible, polymers, illustrated here with poly(4-vinylpyridine) (P4VP), by creating effective (i.e., physical) cross-links via hydrogen bonding or coordination interactions solution using small molecules. addition to P4VP solutions dimethylformamide...

A thermotropic dialkoxy biphenyl liquid crystal, functionalized by a carboxylic acid group at one extremity, is mixed to varying proportions with poly(4-vinylpyridine) (P4VP). The LC-4,6A, characterized monotropic smectic phase and highly ordered or crystalline lamellar formed primarily of dimers. In the mixtures P4VP (studied up acid/pyridine molar ratios 1.0), fluid mesophase suppressed. solid−isotropic transition present above ratio about 0.2, whereas for lower LC-4,6A contents form an...

Abstract The thermotropic phase transitions and the mesophase structure of two long-chain alkyl pyridinium halides are described. From small angle X-ray diffraction, optical microscopy, differential scanning calorimetry dilatometry, single liquid-crystalline found in each material is identified as smectic A. It argued that molecules within a layer oriented alternately packed an interdigitated fashion, with anions sandwiched between rings.

A simple ionic azo-dye polyelectrolyte complex, free of flexible spacer and tail, was prepared from two readily available components. It possesses smectic order subambient to degradation (above 230 °C) provides exceptional photoinduced birefringence (PIB) properties, competitive with if not superior those previously reported all-covalent azo polymers.

Abstract The plasticizing effect of a nonpolar and polar diluent in ionomers was studied by dynamic mechanical methods the glassy to rubbery regions. Specifically, carboxylate sulfonate polystyrene‐based ionomer were investigated with variation diethylbenzene content glycerol content. It found that plasticizes transition formation ionic aggregates as well lowering glass temperature. However, regions are plasticized more than those ionomer. This corroborates results other studies which had...

Abstract Structures of the thermotropic mesophases lead(II) decanoate are reassigned following optical and X-ray diffraction studies. These results, those D.S.C., Raman 207Pb N.M.R. spectroscopy, indicate formation a lower temperature mesophase involving mainly increased lateral disorder, higher Lα (smectic A) phase resulting from chain disordering decreased lead-carboxylate interaction. Comparison experimental thermodynamic data for transitions with theoretical in literature indicates that...

Block copolymer films obtained by dip-coating have been much less studied than those spin-coating, although it is an important industrial process. In our investigations of supramolecular diblock PS–P4VP (∼30 wt % P4VP) dip-coated from THF solutions, we initially found that containing a monohydroxy-functionalized small molecule (SM), 1-naphthol (NOH), dot morphology, whereas monocarboxylic acid-functionalized molecule, 1-naphthoic acid (NCOOH), stripe morphology. The COOH functionality known...

Dip-coating, an important industrial technique, has been underexploited for preparing block copolymer (BC) thin films, such that the knowledge regarding their general characteristics is limited. Here, we present overview of crucial factors determine how BC film morphology evolves as a function dip-coating rate (withdrawal speed) over wide range, illustrated using THF solutions polystyrene-b-poly(4-vinyl pyridine) (PS-P4VP) diblock mixed with two small molecules, naphthol and naphthoic acid,...

It is challenging to fabricate plasmonic nanosensors on high-curvature surfaces with high sensitivity and reproducibility at low cost. Here, we report a facile straightforward strategy, based an in situ growth technique, for fabricating glass nanofibers covered by asymmetric gold nanoparticles (AuNPs) tunable morphologies adjustable spacings, leading much improved surface-enhanced Raman scattering (SERS) because of hotspots generated the AuNP surface irregularities adjacent coupling. First,...