Synthèse et du transfert des autoportants conjugués microporeuses polymères nanomembranes couche par couche
Summary
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.
Abstract
CMP que les grands matériaux de surface ont attiré l'intérêt croissant récemment, en raison de leur grande variabilité dans l'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'une épaisseur et composition souhaitée et la composition même des gradients souhaités.
L'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'interface air-liquide et ensuite transférés par l'intermédiaire d'un revêtement par immersion.
Introduction
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.
Protocol
Representative Results
Discussion
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'une couche d&…
Disclosures
The authors have nothing to disclose.
Acknowledgements
The authors have no acknowledgements.
Materials
| Acetone | VWR BDH Prolabo | 20066.330 | AnalR NORMAPUR |
| Potassium iodide | VWR BDH Prolabo | 26846.292 | AnalR NORMAPUR |
| Ethyl acetate | VWR BDH Prolabo | 23882.321 | AnalR NORMAPUR |
| Tetrahydrofurane (THF) | VWR BDH Prolabo | 28559.320 | HiPerSolv CHROMANORM |
| THF waterfree | Merck Millipore | 1.08107.1001 | SeccoSolv |
| Iodine | Sigma-Aldrich | 20,777-2 | |
| Tetrakis(acetonitrile)copper(I)hexafluoro-phosphate | Sigma-Aldrich | 346276-5G | |
| Poly(methyl methacrylate) 996 kDa (PMMA) | Sigma-Aldrich | 182265-25G | |
| 1.1.1.1 Methanetetrayltetrakis(4-azidobenzene) (TPM-azide) | provided by AK Prof. Bräse. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to9 | ||
| 1.1.1.1 Methanetetrayltetrakis(4-ethinylenebenzene) (TPM-alkyne) | provided by AK Prof. Bräse. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to9 | ||
| 11-thioacetyl-undecaneacid propargylamide | provided by AK Prof. Bräse. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to8 | ||
| gold/titan coated silicium-wafer | Georg Albert PVD, 76857 Silz, Germany | ||
| gold coated mica | Georg Albert PVD, 76857 Silz, Germany |
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