The authors have no acknowledgements.

1. Synthèse de la CMP Thin Films par addition séquentielle <ol><li> Monocouche auto-assemblée (SAM) fonctionnalisation de l&#39;or sur le mica. <ol><li> Préparer la solution 1 mM du 11-thioacétyle-undécane acide propargylique amide 14 dans de l&#39;éthanol (SAM-solution). Mélanger à l&#39;aide d&#39;ultrasons jusqu&#39;à bain solution est claire. Protéger la bouteille de la lumière en utilisant une feuille d&#39;aluminium. </li><li> Obtenir de l&#39;or mica revêtu plaquette sous argon. Après le retrait du récipient de stockage immerger la plaquette de mica directement à la SAM-solution pendant 18 heures. </li><li> Prenez le prêt Au-mica plaquette de la SAM-solution, rincer avec de l&#39;éthanol et sécher sous flux d&#39;azote. Ensuite stocker le substrat protégé de la lumière et sous gaz inerte. </li></ol></li><li> Solutions de précurseur. <ol><li> Peser 18,64 mg de Cu-catalyseur (tétrakis (acétonitrile) cuivre (I) hexafluoro-phosphate), 20,83 mg tétraphénylméthane (TPM) -alkyne et 24,22 mg TPM-azoture et remplir chaque composant dans un ballon Schlenk séparé.Voir la Figure 1 pour TPM-alcyne et TPM-azoture, la synthèse est décrite dans la référence 15. Évacuer et remplir avec un gaz inerte (N 2 ou de l&#39;argon) 3 fois. </li><li> Ajouter 25 ml de tétrahydrofuranne sans eau (THF) à chaque flacon de Schlenk. Protéger les flacons avec TPM-azoture et TPM-alcyne de la lumière en utilisant une feuille d&#39;aluminium. </li></ol></li><li> Appareil pour préparer CMP fabrication. Remarque: L&#39;appareil de synthèse est représentée sur la Figure 2. <ol><li> Utilisez un 250 ml à un col ballon à fond rond. Remplissez 130 ml de THF. Mettre le substrat revêtu préparé avec un alcyne à terminaison SAM dans le compartiment échantillon. Utilisez un porte-échantillon, de sorte que le substrat est en position verticale. </li><li> Raccorder l&#39;appareil à la ligne de Schlenk via la jonction au-dessus du refroidisseur de reflux. </li><li> Évacuer et ventiler avec un gaz inerte 3 fois. </li></ol></li><li> L&#39;addition séquentielle dans des conditions inertes. <ol><li> Réglez le chauffe à 90 ° C et attendre que le THF est refluxant. </li><li> THF laisser sortir du compartiment à échantillon sur l&#39;orifice de sortie au fond du compartiment d&#39;échantillon. Fermez la sortie. </li><li> Donner 1 ml de la solution de l&#39;azide préparé TPM et 0,5 ml de la solution de Cu (I) de catalyseur dans le compartiment d&#39;échantillon par l&#39;intermédiaire du bouchon à vis avec septum. Utiliser une seringue avec une aiguille creuse pour transférer séquentiellement la solution dans le ballon de Schlenk à l&#39;appareil de réaction. Remarque: La séquence n&#39;a pas d&#39;influence de la réaction. </li><li> Attendez environ 30 min. </li><li> Laisser la solution de réaction au-dessus de l&#39;orifice de sortie au fond du compartiment d&#39;échantillon. Fermer la sortie et recueillir le THF condensé pour le rinçage de l&#39;échantillon. Attendez environ 30 min. </li><li> Laisser la solution de rinçage à l&#39;orifice de sortie sur le fond du compartiment d&#39;échantillon. Fermez la sortie. </li><li> Donner 1 ml de la solution préparée TPM-alcyne et 0,5 ml de la solution de Cu (I) de catalyseur dans le compartiment d&#39;échantillon par l&#39;intermédiaire du bouchon à vis avec septum. Utiliser une seringue avec un creuxl&#39;aiguille de transfert à partir de solutions de manière séquentielle le ballon de Schlenk à l&#39;appareil de réaction. Remarque: La séquence n&#39;a pas d&#39;influence de la réaction. </li><li> Attendez environ 30 min. </li><li> Laisser la solution de réaction au-dessus de l&#39;orifice de sortie au fond du compartiment d&#39;échantillon. Fermer la sortie et recueillir le THF condensé pour le rinçage de l&#39;échantillon. Attendez environ 30 min. </li><li> Répéter les étapes 1.4.3 à 1.4.9 jusqu&#39;à ce que la quantité souhaitée de couches est atteinte. Remarque: Une couche est d&#39;environ 1 nm d&#39;épaisseur. </li><li> Sortez le substrat de mica CMP-enduit, rincez-le avec du THF, l&#39;éthanol et le sécher sous un courant d&#39;azote. </li></ol></li></ol> 2. Transfert de CMP nanomembranes <ol><li> Poly (méthacrylate de méthyle) (PMMA) solution. <ol><li> Préparer une solution de 4% (en poids) PMMA (M 996 kDa) dans de l&#39;acétate d&#39;éthyle. Dissoudre le PMMA utilise bain à ultrasons jusqu&#39;à la solution est claire. </li></ol></li><li> Spin revêtement de solution de PMMA. <ol><li> Réglez la tournette à RAtemps mp 10 sec de 0 à 4000 tours par minute, le temps de maintien de 40 secondes et le temps de rampe 10 sec de 4000 à 0 rpm. </li><li> Placez le mica recouvert substrat CMP sur la tournette et de mettre la solution de PMMA sur la plaquette jusqu&#39;à ce qu&#39;elle soit complètement recouverte. Commencez la tournette. </li><li> Après revêtement par centrifugation est terminée, mettre l&#39;échantillon pendant 5 minutes sur une plaque chauffante à 90 ° C. </li><li> Coupez 1 mm à partir de chaque bord du substrat de mica revêtu. Utilisez une paire de ciseaux pour couper les bords. </li></ol></li><li> Transfert de PMMA revêtu CMP nanomembrane. <ol><li> Préparer la solution de I2 / KI / H 2 O (1: 4: 40 m / m / m) et de KI / H 2 O (01:10 m / m). </li><li> Remplissez la solution I 2 / KI H 2 O dans un 150 ml Cristallisoir et remplir la solution KI / H 2 O dans 100 ml Cristallisoir. Mettez l&#39;or CMP revêtu PMMA sur un substrat de mica, de mica en contact à la solution, sur le dessus de l&#39;I 2 / KI / H 2 O solution. Soyez prudent qu&#39;il ne coule pas.Attendez au moins 5 min. </li><li> Mettre le substrat de mica revêtues d&#39;or CMP PMMA de la I 2 / KI / H 2 O solution au-dessus de la solution de KI / H 2 O, avec du mica en contact de solution. Soyez prudent qu&#39;il ne coule pas. Attendez au moins 5 min. </li><li> Remplir d&#39;eau distillée dans un 250 ml Cristallisoir. Décoller la / CMP film / or PMMA du mica. Pour ce faire, légèrement en immergeant le substrat, à partir d&#39;un bord, dans l&#39;eau distillée. Maintenir le substrat de sorte que le mica est orientée à l&#39;eau. Remarque: La procédure est représentée sur la Figure 3. </li><li> Dip-enduire le PMMA / CMP / or sur la tranche de silicium. Pour ce faire, l&#39;approche du PMMA / CMP / or lentement avec la plaquette jusqu&#39;à ce qu&#39;il touche bord de la piscine PMMA / membrane / or CMP. Extraire la plaquette de silicium lentement, une fois que le Si-plaquette est en contact avec le / CMP / membrane d&#39;or PMMA. </li><li> Bande de la / CMP / film d&#39;or PMMA hors de la tranche de silicium. Pour ce faire, en plongeant légèrement le substrat, à partir d&#39;un edge, dans le I 2 / KI / H 2 O solution. Attendre 15 min. </li><li> Après l&#39;or est entièrement gravée, transférer la membrane PMMA / CMP à l&#39;eau par l&#39;intermédiaire de la tranche de silicium. Attendre 15 min. </li><li> Répétez l&#39;étape 2.3.7 trois fois pour laver la membrane avec de l&#39;eau. </li><li> Transférer la membrane PMMA / CMP lavé sur le substrat souhaité, par exemple, une lame de microscope ou une tranche de silicium revêtue d&#39;or, par le procédé mentionné dans l&#39;étape 2.3.5. Laissez le PMMA / CMP substrat sécher à l&#39;air pendant au moins 2 h. </li></ol></li><li> Dissolution de PMMA. <ol><li> Mettez le substrat PMMA / CMP dans de l&#39;acétone. Attendre 30 min. Sortez le substrat et le rincer avec de l&#39;acétone. </li><li> Répétez l&#39;étape 2.4.1 trois fois. </li><li> Laissez le CMP substrat sécher pendant au moins 2 h. </li></ol></li></ol>

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A., W&#246;ll, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=MOF+thin+films:+existing+and+future+applications.">MOF thin films: existing and future applications.</a> Chemical Society Reviews. 40 (2), 1081-1106 (2011).</li><li>Liu, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deposition+of+Metal-Organic+Frameworks+by+Liquid-Phase+Epitaxy:+The+Influence+of+Substrate+Functional+Group+Density+on+Film+Orientation.">Deposition of Metal-Organic Frameworks by Liquid-Phase Epitaxy: The Influence of Substrate Functional Group Density on Film Orientation.</a> Materials. 5 (9), 1581-1592 (2012).</li><li>Such, G. K., Quinn, J. F., Quinn, A., Tjipto, E., Caruso, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assembly+of+Ultrathin+Polymer+Multilayer+Films+by+Click+Chemistry.">Assembly of Ultrathin Polymer Multilayer Films by Click Chemistry.</a> Journal of the American Chemical Society. 128 (29), 9318-9319 (2006).</li><li>Ai, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+Nanomembranes+(CNMs)+Supported+by+Polymer:+Mechanics+and+Gas+Permeation.">Carbon Nanomembranes (CNMs) Supported by Polymer: Mechanics and Gas Permeation.</a> Advanced Materials. 26 (21), 3421-3426 (2014).</li><li>Jiang, J. -. X., Cooper, A. 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J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoporous+organic+polymer+networks.">Nanoporous organic polymer networks.</a> Progress in Polymer Science. 37 (4), 530-563 (2012).</li><li>Muller, T., Br&#228;se, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Click+Chemistry+Finds+Its+Way+into+Covalent+Porous+Organic+Materials.">Click Chemistry Finds Its Way into Covalent Porous Organic Materials.</a> Angewandte Chemie International Edition. 50 (50), 11844-11845 (2011).</li><li>Tsotsalas, M., Addicoat, M. 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The authors have nothing to disclose.

Pour la synthèse de la CMP-couche de la solution du catalyseur doit être frais. Un catalyseur cassé (c.-à-oxydée) est indiqué par une coloration bleue de la solution. La nouvelle solution est incolore. Un point crucial est de couper les bords du substrat de mica après spin coating PMMA. Aussi des défauts dans le substrat doivent être coupés, à savoir, chaque spot était le PMMA peut entrer en contact avec le substrat de mica, à cause d&#39;une couche d&...

The preparation of ultra-thin polymer membranes is of high interest for applications in gas separation and nanofiltration. Challenges in the synthesis are represented by (a) the control of the membrane thickness and the homogeneity and (b) transfer of such fragile membranes. To overcome challenge (a), molecular layer-by-layer synthesis1 has shown great promise in controlling the thickness and homogeneity of thin films grown at the solid-liquid interface.2,3 Controlling the number of layers linearly controls the film thickness. The l-b-l method has been successfully used to fabricate surface mounted metal organic frameworks (SURMOFs),4-7 also the synthesis of thin polymer films via l-b-l reaction of polymer chains was demonstrated.8 The challenge (b) concerns the handling of these ultra-thin membranes. To avoid rupture or wrinkling of the nanomembranes sacrificial supports of coatings have shown great promise. 9
Here we will present a detailed protocol for synthesis of conjugated microporous polymer (CMP)10-13 thin films through sequential addition of the molecular building blocks, with desired thickness and composition. The preparation of free-standing CMP nanomembranes is achieved by using a sacrificial support. To handle and transfer the CMP nanomembranes to other supports we will describe a simple protocol to protect the membranes with sacrificial coatings and their upfloating to the liquid air interface and subsequent transfer using dip-coating.

<table>
	<tbody>
		<tr>
			<td>Acetone</td>
			<td>VWR BDH Prolabo</td>
			<td>20066.330</td>
			<td>AnalR NORMAPUR</td>
		</tr>
		<tr>
			<td>Potassium iodide</td>
			<td>VWR BDH Prolabo</td>
			<td>26846.292</td>
			<td>AnalR NORMAPUR</td>
		</tr>
		<tr>
			<td>Ethyl acetate</td>
			<td>VWR BDH Prolabo</td>
			<td>23882.321</td>
			<td>AnalR NORMAPUR</td>
		</tr>
		<tr>
			<td>Tetrahydrofurane (THF)</td>
			<td>VWR BDH Prolabo</td>
			<td>28559.320</td>
			<td>HiPerSolv CHROMANORM</td>
		</tr>
		<tr>
			<td>THF waterfree</td>
			<td>Merck Millipore</td>
			<td>1.08107.1001</td>
			<td>SeccoSolv</td>
		</tr>
		<tr>
			<td>Iodine</td>
			<td>Sigma-Aldrich</td>
			<td>20,777-2</td>
			<td></td>
		</tr>
		<tr>
			<td>Tetrakis(acetonitrile)copper(I)hexafluoro-phosphate</td>
			<td>Sigma-Aldrich</td>
			<td>346276-5G</td>
			<td></td>
		</tr>
		<tr>
			<td>Poly(methyl methacrylate) 996 kDa (PMMA)</td>
			<td>Sigma-Aldrich</td>
			<td>182265-25G</td>
			<td></td>
		</tr>
		<tr>
			<td>1.1.1.1 Methanetetrayltetrakis(4-azidobenzene) (TPM-azide)</td>
			<td></td>
			<td></td>
			<td>provided by AK Prof. Br&#228;se. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to9</td>
		</tr>
		<tr>
			<td>1.1.1.1 Methanetetrayltetrakis(4-ethinylenebenzene) (TPM-alkyne)</td>
			<td></td>
			<td></td>
			<td>provided by AK Prof. Br&#228;se. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to9</td>
		</tr>
		<tr>
			<td>11-thioacetyl-undecaneacid propargylamide</td>
			<td></td>
			<td></td>
			<td>provided by AK Prof. Br&#228;se. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to8</td>
		</tr>
		<tr>
			<td>gold/titan coated silicium-wafer</td>
			<td>Georg Albert PVD, 76857 Silz, Germany</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>gold coated mica</td>
			<td>Georg Albert PVD, 76857 Silz, Germany</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

layer-by-layer synthesis and transfer of freestanding conjugated microporous polymer nanomembranes

CMP que les grands matériaux de surface ont attiré l&#39;intérêt croissant récemment, en raison de leur grande variabilité dans l&#39;incorporation de groupes fonctionnels en combinaison avec leur stabilité chimique et thermique exceptionnelle et de faibles densités. Cependant, leur nature insoluble provoque des problèmes dans leur traitement, car les techniques habituellement utilisés tels que le revêtement par centrifugation ne sont pas disponibles. Surtout pour les applications de la membrane, où le traitement du CMP que films minces est souhaitable, les problèmes de traitement ont entravé leur application commerciale. Nous décrivons ici la synthèse interfaciale de films minces substrats fonctionnalisés CMP sur via (LBL) la synthèse moléculaire couche par couche. Ce procédé permet la préparation de films d&#39;une épaisseur et composition souhaitée et la composition même des gradients souhaités. L&#39;utilisation de supports sacrificielles permet la préparation de membranes autoportantes par dissolution du support aprèsla synthèse. Pour gérer ces ultra-minces membranes autoportantes la protection de revêtements sacrificiels montré une grande promesse, pour éviter une rupture des nanomembranes. Pour transférer les nanomembranes sur le substrat désiré, les membranes sont recouvertes upfloated à l&#39;interface air-liquide et ensuite transférés par l&#39;intermédiaire d&#39;un revêtement par immersion.

Les membranes sont caractérisées par spectroscopie d&#39;absorption infrarouge de réflexion (IRRAS). 16 La figure 4 montre des spectres de-IRRA un CMP-membrane transféré sur une plaquette d&#39;or. Bandes typiques de la vibrations du squelette aromatique sont à 1,605 cm -1, 1,515 cm -1 et 1,412 cm -1. Alcyne et azoture groupes ayant pas réagi peuvent être observées par les bandes caractéristiques à 2125 cm -1 et 1227 cm -1. <st...

Watch this Scientific Journal Video about Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes at JoVE.com

Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes

In this paper we describe the interfacial synthesis of conjugated microporous polymers (CMP) on sacrificial substrates, and the dissolution of the substrate for the preparation of freestanding CMP nanomembranes. In addition, we will describe how the fragile nanomembranes can be transferred to other substrates.

Synthèse et du transfert des autoportants conjugués microporeuses polymères nanomembranes couche par couche

CMP as large surface area materials have attracted growing interest recently, due to their high variability in the incorporation of functional groups in ...

layer-layer-synthesis-transfer-freestanding-conjugated-microporous

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9.3K vues.  Karlsruhe Institute of Technology. In this paper we describe the interfacial synthesis of conjugated microporous polymers (CMP) on sacrificial substrates, and the dissolution of the substrate for the preparation of freestanding CMP nanomembranes. In addition, we will describe how the fragile nanomembranes can be transferred to other substrates.

Vidéo: Layer-by-layer Synthesis and Transfer of Freestanding Conjugated Microporous Polymer Nanomembranes

Confocal Imaging of Confined Quiescent and Flowing Colloid-polymer Mixtures

The behavior of confined colloidal suspensions with attractive interparticle interactions is critical to the rational design of materials for directed assembly1-3, drug delivery4, improved hydrocarbon recovery5-7, and flowable electrodes for energy storage8. Suspensions containing fluorescent colloids and non-adsorbing polymers are appealing model systems, as the ratio of the polymer radius of gyration to the particle radius&#160;and concentration of polymer control the range and strength of the interparticle attraction, respectively. By tuning the polymer properties and the volume fraction of the colloids, colloid fluids, fluids of clusters, gels, crystals, and glasses can be obtained9.&#160;Confocal microscopy, a variant of fluorescence microscopy, allows an optically transparent and fluorescent sample to be imaged with high spatial and temporal resolution in three dimensions. In this technique, a small pinhole or slit blocks the emitted fluorescent light from regions of the sample that are outside the focal volume of the microscope optical system. As a result, only a thin section of the sample in the focal plane is imaged. This technique is particularly well suited to probe the structure and dynamics in dense colloidal suspensions at the single-particle scale: the particles are large enough to be resolved using visible light and diffuse slowly enough to be captured at typical scan speeds of commercial confocal systems10. Improvements in scan speeds and analysis algorithms have also enabled quantitative confocal imaging of flowing suspensions11-16,37.&#160;In this paper, we demonstrate confocal microscopy experiments to probe the confined phase behavior and flow properties of colloid-polymer mixtures. We first prepare colloid-polymer mixtures that are density- and refractive-index matched. Next, we report a standard protocol for imaging quiescent dense colloid-polymer mixtures under varying confinement in thin wedge-shaped cells. Finally, we demonstrate a protocol for imaging colloid-polymer mixtures during microchannel flow.

Confocal microscopy is used to image quiescent and flowing colloid-polymer mixtures, which are studied as model systems for attractive suspensions. Image analysis algorithms are used to calculate structural and dynamic metrics for the colloidal particles that measure changes due to geometric confinement.

Imagerie confocale de clos de repos et Flowing mélanges colloïdes-polymères

The behavior of confined colloidal suspensions with attractive interparticle interactions is critical to the rational design of materials for directed ...

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Chimie

Fabrication of Large-area Free-standing Ultrathin Polymer Films

This procedure describes a method for the fabrication of large-area and ultrathin free-standing polymer films. Typically, ultrathin films are prepared using either sacrificial layers, which may damage the film or affect its mechanical properties, or they are made on freshly cleaved mica, a substrate that is difficult to scale. Further, the size of ultrathin film is typically limited to a few square millimeters. In this method, we modify a surface with a polyelectrolyte that alters the strength of adhesion between polymer and deposition substrate. The polyelectrolyte can be shown to remain on the wafer using spectroscopy, and a treated wafer can be used to produce multiple films, indicating that at best minimal amounts of the polyelectrolyte are added to the film. The process has thus far been shown to be limited in scalability only by the size of the coating equipment, and is expected to be readily scalable to industrial processes. In this study, the protocol for making the solutions, preparing the deposition surface, and producing the films is described.

We describe a method for the fabrication of large-area (up to 13 cm diameter) and ultrathin (as thin as 8 nm) polymer films. Instead of using a sacrificial interlayer to delaminate the film from its substrate, we use a self-limiting surface treatment suitable for arbitrarily large areas.

Fabrication de grande Zone de libre-debout ultraminces films polymères

This procedure describes a method for the fabrication of large-area and ultrathin free-standing polymer films.  Typically, ultrathin films are prepared ...

Preparation of Highly Porous Coordination Polymer Coatings on Macroporous Polymer Monoliths for Enhanced Enrichment of Phosphopeptides

We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous polymer monoliths. The developed approach is based on the preparation of a macroporous polymer containing carboxylic acid functional groups and the subsequent step-by-step solution-based controlled growth of a layer of a porous coordination polymer on the surface of the pores of the polymer monolith. The prepared metal-organic polymer hybrid has a high specific micropore surface area. The amount of iron(III) sites is enhanced through metal-organic coordination on the surface of the pores of the functional polymer support. The increase of metal sites is related to the number of iterations of the coating process.
The developed preparation scheme is easily adapted to a capillary column format. The functional porous polymer is prepared as a self-contained single-block porous monolith within the capillary, yielding a flow-through separation device with excellent flow permeability and modest back-pressure. The metal-organic polymer hybrid column showed excellent performance for the enrichment of phosphopeptides from digested proteins and their subsequent detection using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The presented experimental protocol is highly versatile, and can be easily implemented to different organic polymer supports and coatings with a plethora of porous coordination polymers and metal-organic frameworks for multiple purification and/or separation applications.

A procedure for the preparation of porous hybrid separation media composed of a macroporous polymer monolith internally coated by a high surface area microporous coordination polymer is presented.

Préparation de la grande porosité de coordination Polymer Coatings sur macroporeuses Polymer monolithes pour enrichissement accrue des Phosphopeptides

We describe a protocol for the preparation of hybrid materials based on highly porous coordination polymer coatings on the internal surface of macroporous ...

Photodynamic Therapy with Blended Conducting Polymer/Fullerene Nanoparticle Photosensitizers

In this article a method for the fabrication and reproducible in-vitro evaluation of conducting polymer nanoparticles blended with fullerene as the next generation photosensitizers for Photodynamic Therapy (PDT) is reported. The nanoparticles are formed by hydrophobic interaction of the semiconducting polymer MEH-PPV (poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene]) with the fullerene PCBM (phenyl-C61-butyric acid methyl ester) in the presence of a non-compatible solvent. MEH-PPV has a high extinction coefficient that leads to high rates of triplet formation, and efficient charge and energy transfer to the fullerene PCBM. The latter processes enhance the efficiency of the PDT system through fullerene assisted triplet and radical formation, and ultrafast deactivation of MEH-PPV excited stated. The results reported here show that this nanoparticle PDT sensitizing system is highly effective and shows unexpected specificity to cancer cell lines.

This protocol describes a method for the fabrication of conducting polymer nanoparticles blended with fullerene. These nanoparticles were investigated for their potential use as a next generation photosensitizers for Photodynamic Therapy (PDT).

La thérapie photodynamique avec Blended polymère conducteur / Fullerene nanoparticules photosensibilisants

In this article a method for the fabrication and reproducible in-vitro evaluation of conducting polymer nanoparticles blended with fullerene as the next ...

The Preparation and Properties of Thermo-reversibly Cross-linked Rubber Via Diels-Alder Chemistry

A method for using Diels Alder thermo-reversible chemistry as cross-linking tool for rubber products is demonstrated. In this work, a commercial ethylene-propylene rubber, grafted with maleic anhydride, is thermo-reversibly cross-linked in two steps. The pending anhydride moieties are first modified with furfurylamine to graft furan groups to the rubber backbone. These pendant furan groups are then cross-linked with a bis-maleimide via a Diels-Alder coupling reaction. Both reactions can be performed under a broad range of experimental conditions and can easily be applied on a large scale. The material properties of the resulting Diels-Alder cross-linked rubbers are similar to a peroxide-cured ethylene/propylene/diene rubber (EPDM) reference. The cross-links break at elevated temperatures (&#62; 150 &#176;C) via the retro-Diels-Alder reaction and can be reformed by thermal annealing at lower temperatures (50-70 &#176;C). Reversibility of the system was proven with infrared spectroscopy, solubility tests and mechanical properties. Recyclability of the material was also shown in a practical way, i.e., by cutting a cross-linked sample into small parts and compression molding them into new samples displaying comparable mechanical properties, which is not possible for conventionally cross-linked rubbers.

A simple two-step approach involving rubber modification and cross-linking yields fully reworkable, elastic rubber products.

La préparation et les propriétés des Thermo-réversiblement réticulé Rubber Chemistry Via Diels-Alder

A method for using Diels Alder thermo-reversible chemistry as cross-linking tool for rubber products is demonstrated. In this work, a commercial ...

Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering

We demonstrate a protocol to effectively monitor the gelation process of a high concentration solution of conjugated polymer both in the presence and absence of white light exposure. By instituting a controlled temperature ramp, the gelation of these materials can be precisely monitored as they proceed through this structural evolution, which effectively mirrors the conditions experienced during the solution deposition phase of organic electronic device fabrication. Using small angle neutron scattering (SANS) and ultra-small angle neutron scattering (USANS) along with appropriate fitting protocols we quantify the evolution of select structural parameters throughout this process. Thorough analysis indicates that continued light exposure throughout the gelation process significantly alters the structure of the ultimately formed gel. Specifically, the aggregation process of poly(3-hexylthiophene-2,5-diyl) (P3HT) nano-scale aggregates is negatively affected by the presence of illumination, ultimately resulting in the retardation of growth in conjugated polymer microstructures and the formation of smaller scale macro-aggregate clusters.

A protocol for the analysis of gels formed from the optoelectronic conjugated polymer poly(3-hexylthiophene-2,5-diyl) (P3HT) using small and ultra-small angle neutron scattering in both the presence and absence of illumination is presented.

Surveillance des effets de l’éclairement sur la Structure des Gels de polymères conjugués à l’aide de la diffusion des neutrons

We demonstrate a protocol to effectively monitor the gelation process of a high concentration solution of conjugated polymer both in the presence and ...

Microfluidic Dry-spinning and Characterization of Regenerated Silk Fibroin Fibers

The protocol demonstrates a method for mimicking the spinning process of silkworm. In the native spinning process, the contracting spinning duct enables the silk proteins to be compact and ordered by shearing and elongation forces. Here, a biomimetic microfluidic channel was designed to mimic the specific geometry of the spinning duct of the silkworm. Regenerated silk fibroin (RSF) spinning doped with high concentration, was extruded through the microchannel to dry-spin fibers at ambient temperature and pressure. In the post-treated process, the as-spun fibers were drawn and stored in ethanol aqueous solution. Synchrotron radiation wide-angle X-ray diffraction (SR-WAXD) technology was used to investigate the microstructure of single RSF fibers, which were fixed to a sample holder with the RSF fiber axis normal to the microbeam of the X-ray. The crystallinity, crystallite size, and crystalline orientation of the fiber were calculated from the WAXD data. The diffraction arcs near the equator of the two-dimensional WAXD pattern indicate that the post-treated RSF fiber has a high orientation degree.

A protocol for the microfluidic spinning and microstructure characterization of regenerated silk fibroin monofilament is presented.

Microfluidique sec-spinning et caractérisation des fibres régénérées fibroïne de soie

The protocol demonstrates a method for mimicking the spinning process of silkworm. In the native spinning process, the contracting spinning duct enables ...

Time-resolved Photophysical Characterization of Triplet-harvesting Organic Compounds at an Oxygen-free Environment Using an iCCD Camera

Here, we present a sensible method of the acquisition and analysis of time-resolved photoluminescence using an ultrafast iCCD camera. This system enables the acquisition of photoluminescence spectra covering the time regime from nanoseconds up to 0.1 s. This enables us to follow the changes in the intensity (decay) and emission of the spectra over time. Using this method, it is possible to study diverse photophysical phenomena, such as the emission of phosphorescence, and the contributions of prompt and delayed fluorescence in molecules showing thermally activated delayed fluorescence (TADF). Remarkably, all spectra and decays are obtained in a single experiment. This can be done for solids (thin film, powder, crystal) and liquid samples, where the only limitations are the spectral sensitivity of the camera and the excitation wavelength (532 nm, 355 nm, 337 nm, and 266 nm). This technique is, thus, very important when investigating the excited state dynamics in organic emitters for their application in organic light-emitting diodes and other areas where triplet harvesting is of paramount importance. Since triplet states are strongly quenched by oxygen, emitters with efficient TADF luminescence, or those showing room temperature phosphorescence (RTP), must be correctly prepared in order to remove any dissolved oxygen from solutions and films. Otherwise, no long-lived emission will be observed. The method of degassing solid samples as presented in this work is basic and simple, but the degassing of liquid samples creates additional difficulties and is particularly interesting. A method of minimizing solvent loss and changing the sample concentration, while still enabling to remove oxygen in a very efficient and a repeatable manner, is presented in this work.

Here, we present a method of the spectroscopic characterization of organic molecules by means of time-resolved photoluminescence spectroscopy on the nanosecond-to-millisecond timescale in oxygen-free conditions. Methods to efficiently remove oxygen from the samples and, thus, limit luminescence quenching are also described.

Résolution temporelle des composés organiques Photophysiques caractérisation du Triplet-récolte à un sans oxygène environnement utilisant un iCCD caméra

Here, we present a sensible method of the acquisition and analysis of time-resolved photoluminescence using an ultrafast iCCD camera. This system enables ...

Raman and IR Spectroelectrochemical Methods as Tools to Analyze Conjugated Organic Compounds

In the presented work, two spectroelectrochemical techniques are discussed as tools for the analysis of the structural changes occurring in the molecule on the vibrational level of energy. Raman and IR spectroelectrochemistry can be used for advanced characterization of the structural changes in the organic electroactive compounds. Here, the step-by-step analysis by means of Raman and IR spectroelectrochemistry is shown. Raman and IR spectroelectrochemical techniques provide complementary information about structural changes occurring during an electrochemical process, i.e. allows for the investigation of redox processes and their products. The examples of IR and Raman spectroelectrochemical analysis are presented, in which the products of the redox reactions, both in solution and solid state, are identified.

A protocol of step-by-step Raman and IR spectroelectrochemical analysis is presented.

Raman et IR spectroélectrochimiques méthodes comme outils pour analyser les composés organiques conjugués

In the presented work, two spectroelectrochemical techniques are discussed as tools for the analysis of the structural changes occurring in the molecule ...

Reactive Vapor Deposition of Conjugated Polymer Films on Arbitrary Substrates

We demonstrate a method of conformally coating conjugated polymers on arbitrary substrates using a custom-designed, low-pressure reaction chamber. Conductive polymers, poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3,4-propylenedioxythiophene) (PProDOT), and a semiconducting polymer, poly(thieno[3,2-b]thiophene) (PTT), were deposited on unconventional highly-disordered and textured substrates with high surface areas, such as paper, towels and fabrics. This reported deposition chamber is an improvement of previous vapor reactors because our system can accommodate both volatile and nonvolatile monomers, such as 3,4-propylenedioxythiophene and thieno[3,2-b]thiophene. Utilization of both solid and liquid oxidants are also demonstrated. One limitation of this method is that it lacks sophisticated in situ thickness monitors. Polymer coatings made by the commonly used solution-based coating methods, such as spin-coating and surface grafting, are often not uniform or susceptible to mechanical degradation. This reported vapor phase deposition method overcomes those drawbacks and is a strong alternative to common solution-based coating methods. Notably, polymer films coated by the reported method are uniform and conformal on rough surfaces, even at a micrometer scale. This feature allows for future application of vapor deposited polymers in electronics devices on flexible and highly textured substrates.

This paper presents a protocol for reactive vapor deposition of poly(3,4-ethylenedioxythiophene), poly(3,4-propylenedioxythiophene), and poly(thieno[3,2-b]thiophene) films on glass slides and rough substrates, such as textiles and paper.