Layer-by-layer synthese en de overdracht van Vrijstaande geconjugeerde Microporous Polymer Nanomembranes
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 zo groot oppervlak materialen aangetrokken groeiende belangstelling voor kort vanwege hun hoge variabiliteit in de inbouw van functionele groepen in combinatie met hun uitstekende thermische en chemische stabiliteit en lage dichtheden. Echter, hun onoplosbaarheid veroorzaakt problemen bij de verwerking omdat gewoonlijk gebruikte technieken zoals spin coaten niet beschikbaar. Speciaal voor membraan toepassingen, waarbij de verwerking van CMP als dunne films wenselijk is, hebben de verwerking problemen hun commerciële toepassing gehinderd.
Hier beschrijven we het grensvlak synthese van CMP dunne films op gefunctionaliseerde substraten via moleculaire laag-voor-laag (LBL) synthese. Deze werkwijze maakt de bereiding van folies met de gewenste dikte en samenstelling en zelfs gewenste samenstelling gradiënten.
Het gebruik opofferingskolommen dragers maakt de bereiding van vrijstaande membranen door oplossen van de drager nade synthese. Om dergelijke ultradunne vrijstaande membranen omgaan met de bescherming met opofferende coatings toonden grote belofte, om breuk van de nanomembranes voorkomen. Om de nanomembranes overbrengen naar de gewenste substraat, worden de gecoate membranen upfloated in de lucht-vloeistof-interface en vervolgens overgebracht via dip coating.
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
Voor de synthese van CMP-film de oplossing van de katalysator vers. Een gebroken katalysator (dwz geoxideerd) wordt aangeduid met een blauwe kleur van de oplossing. De verse oplossing is kleurloos.
Cruciaal is om de randen van het mica substraat afgesneden nadat spinbekleding PMMA. Ook defecten in het substraat worden gesneden, dat wil zeggen, elke vlek werden de PMMA kan in contact komen met het mica substraat vanwege een ontbrekende goudlaag. Anders is het goud laag kan n…
Declarações
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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