The authors have no acknowledgements.

Sıralı ilavesi yoluyla CMP İnce Filmlerin 1. Sentezi <ol><li> Mika altın Kendinden montajlı tek tabaka (SAM) işlevsellik. <ol><li> Etanol 11-tioasetil-undekan asit-propargyl amid 14 1 mM çözeltisi (SAM-çözüm) hazırlayın. Çözelti berrak olana kadar ultrasonik banyo kullanarak karıştırın. Alüminyum folyo kullanarak ışık şişeyi koruyun. </li><li> Argon altında, altın kaplı mika gofret elde edilir. Depolama kabından çekilmesinden sonra 18 saat boyunca SAM-çözümün doğrudan mika gofret batırmayın. </li><li> SAM-çözümün dışında hazırlanan Au-mika gofret alın azot akımı altında etanol ve kuru ile durulayın. Daha sonra ışık ve inert gaz altında korunan substrat saklayın. </li></ol></li><li> Öncü çözümleri. <ol><li> 18,64 mg Cu-katalizörün (tetrakis (asetonitril) bakır (I) &#39;in sentezi fosfat), 20,83 mg tetraphenylmethane (TPM) -alkyne ve 24,22 mg TPM azid tartılır ve ayrı bir Schlenk şişesi içine, her bir bileşen doldurun.TPM alkin ve TPM azid için bakınız Şekil 1., sentez Başvurusu 15 tarif edilmiştir. Boşaltın ve inert gaz (N2 veya argon) ile 3 kez doldurun. </li><li> Her bir Schlenk şişesine 25 ml su içermeyen tetrahidrofuran (THF) ilave edilir. Alüminyum folyo kullanarak ışık TPM azid ve TPM-alkin ile şişeler koruyun. </li></ol></li><li> CMP imalatı için aparat hazırlayın. Not: Sentez cihazı, Şekil 2 &#39;de gösterilmiştir. <ol><li> Bir 250 ml&#39;lik tek boyunlu, yuvarlak tabanlı bir şişeye kullanın. 130 mi THF içinde doldurun. Alkin ile kaplanmış hazırlanan alt tabaka koymak örnek bölmesine SAM sonlandırıldı. Alt-tabaka dik duran, böylece örnek tutucu kullanın. </li><li> Reflü soğutucusunun üstündeki kavşağında yolu ile savurma hattına cihazı bağlayın. </li><li> 3 kez boşaltın ve inert gaz ile havalandırın. </li></ol></li><li> Soy gaz koşulları altında Sıralı ek. <ol><li> 90 ° C&#39;ye kadar ısıtıcı ayarlayın ve THF yeniden olana kadar bekleyineritken. </li><li> Numune bölmesinin alt kısmındaki çıkışında üzerinde numune bölmesinden THF dışarı edelim. Çıkışını kapatın. </li><li> Hazırlanan TPM azid çözeltisi 1 ml ve septumla vidalı kapakla numune kompartımanı Cu (I) &#39;in katalizör çözeltisi 0,5 ml ver. Reaksiyon aparatı savurma şişesi çözümleri sırayla aktarmak için bir oyuk bir iğne ile bir şırınga kullanın. Not: dizisi reaksiyona herhangi bir etkisi yoktur. </li><li> Yaklaşık 30 dakika bekleyin. </li><li> Numune bölmesinin alt kısmındaki çıkışında üzerinde reaksiyon çözüm olsun. Çıkışını kapatın ve numune durulama özet THF toplamak. Yaklaşık 30 dakika bekleyin. </li><li> Numune bölmesinin alt kısmındaki çıkışında üzerinde durulama çözüm olsun. Çıkışını kapatın. </li><li> Hazırlanan TPM alkin çözeltisi 1 ml ve septumla vidalı kapakla numune kompartımanı Cu (I) &#39;in katalizör çözeltisi 0,5 ml ver. Içi boş bir şırınga kullanınİğne Reaksiyon cihazına bir Schlenk şişesi çözeltiler sıralı olarak aktarmak için kullanılır. Not: dizisi reaksiyona herhangi bir etkisi yoktur. </li><li> Yaklaşık 30 dakika bekleyin. </li><li> Numune bölmesinin alt kısmındaki çıkışında üzerinde reaksiyon çözüm olsun. Çıkışını kapatın ve numune durulama özet THF toplamak. Yaklaşık 30 dakika bekleyin. </li><li> Tekrarlayın tabakalarının istenilen miktara varıncaya kadar 1.4.9 için 1.4.3 adımlar. Not: Bir katman yaklaşık olarak 1 nm kalınlığındadır. </li><li> , CMP-kaplı mika substrat çıkarıp THF, etanol ile durulayın ve azot akımı altında kurutun. </li></ol></li></ol> CMP Nanomembranlar 2. Transferi <ol><li> Poli (metil metakrilat) (PMMA) çözeltisi eklendi. <ol><li> Etil asetat içinde% 4 (ağırlık) PMMA (M 996 kDa) ihtiva eden bir çözelti hazırlayın. Çözelti berrak olana kadar PMMA ultrasonik banyo kullanarak eritin. </li></ol></li><li> PMMA çözümünün Spin kaplama. <ol><li> Ra spin kaplayıcı ayarlamp süresi 0 rpm 4000 ila 10 saniye, saat 40 sn tutup 4,000 0 rpm zamanı 10 sn rampa. </li><li> Spin kaplayıcı CMP kaplı mika substrat yerleştirin ve tamamen kaplıdır kadar gofret PMMA çözümünü koydu. Spin kaplayıcı başlatın. </li><li> Döndürerek kaplama tamamlandıktan sonra, 90 ° C&#39;de bir ısıtma plakası üzerinde 5 dakika boyunca numune koydu. </li><li> Kaplanmış mika substrat her kenarından 1 mm kesti. Kenarları kesmek için bir makas kullanın. </li></ol></li><li> PMMA Devri CMP nanomembrane kaplı. <ol><li> Ve KI / H2O (1:10 a / a) I 2 / KI / H 2 solüsyonu O (: 4 40 a / a / a 1) hazırlayın. </li><li> Çanak kristalleştirilmesi 150 ml I2 / KI H2O çözeltisi doldurun ve çanak kristalleştirilmesi 100 ml KI / H2O çözeltisi doldurun. I 2 / KI / H2O çözeltisi üzerine, çözeltiye temas mika, mika alt tabaka üzerine kaplanmış PMMA CMP altın koyun. O lavabo olmadığını dikkatli olun.En az 5 dakika bekleyin. </li><li> I 2 / KI / H2 çözeltisine temas mika KI / H2O çözeltisi üzerine solüsyon, PMMA kaplı CMP altın mika alt-tabakanın koyun. O lavabo olmadığını dikkatli olun. En az 5 dakika bekleyin. </li><li> Çanak kristalleştirilmesi 250 ml damıtılmış su doldurun. Mika gelen PMMA / CMP / altın filmi atacakmısınız. Hafif damıtılmış su içinde, bir kenarından başlayarak, alt-tabakanın içine daldırılması yapın. Mika suya bakacak şekilde alt tabakayı tutun. Not: süreci Şekil 3 &#39;de gösterilmiştir. </li><li> Dip kat silikon gofret PMMA / CMP / altın. O yüzme PMMA / CMP / altın zarın kenarına temas edene kadar gofret ile yavaş yavaş PMMA / CMP / altın yaklaşarak bunu yapın. Si-gofret PMMA / CMP / altın zar ile temas halinde olduğu zamanlar, yavaş yavaş silikon gofret çekin. </li><li> Silikon gofret PMMA / CMP / altın filmi atacakmısınız. Biraz tek ed itibaren, alt tabakayı daldırarak yapınge, I 2 / KI / H 2 O çözüm. 15 dakika bekleyin. </li><li> Altın tamamen kazınmış sonra silikon vasıtasıyla suya PMMA / CMP zarı aktarın. 15 dakika bekleyin. </li><li> Üç kez adımı yineleyin 2.3.7 suyla membran yıkayın. </li><li> Aşama 2.3.5 belirtilen yöntemle, istenen alt-tabaka, örneğin, bir mikroskop lamı veya altın kaplama silikon yıkanarak PMMA / CMP membran aktarın. En az 2 saat süreyle havada PMMA / CMP substrat kurumasını bekleyin. </li></ol></li><li> PMMA Feshi. <ol><li> Aseton PMMA / CMP substratı koyun. 30 dakika bekleyin. Substrat çıkarın ve aseton ile durulayın. </li><li> Adımı yineleyin 2.4.1 üç kez. </li><li> En az 2 saat CMP substrat kurumasını bekleyin. </li></ol></li></ol>

<ol><li>Lindemann, P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Preparation+of+Freestanding+Conjugated+Microporous+Polymer+Nanomembranes+for+Gas+Separation%5BTitle%5D)+AND+%22Chemistry+of+Materials%22%5BJournal%5D)">Preparation of Freestanding Conjugated Microporous Polymer Nanomembranes for Gas Separation.</a> Chemistry of Materials. 26 (24), 7193-71 (2014).</li>
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<li>Vonhören, B., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Ultrafast+Layer-by-Layer+Assembly+of+Thin+Organic+Films+Based+on+Triazolinedione+Click+Chemistry%5BTitle%5D)+AND+%22ACS+Macro+Letters%22%5BJournal%5D)">Ultrafast Layer-by-Layer Assembly of Thin Organic Films Based on Triazolinedione Click Chemistry.</a> ACS Macro Letters. 4 (3), 331-334 (2015).</li>
<li>Shekhah, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Step-by-Step+Route+for+the+Synthesis+of+Metal%E2%88%92Organic+Frameworks%5BTitle%5D)+AND+%22Journal+of+the+American+Chemical+Society%22%5BJournal%5D)">Step-by-Step Route for the Synthesis of Metal−Organic Frameworks.</a> Journal of the American Chemical Society. 129 (49), 15118-15119 (2007).</li>
<li>Shekhah, O., Wang, H., Zacher, D., Fischer, R. A., Wöll, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Growth+Mechanism+of+Metal%E2%80%93Organic+Frameworks%3A+Insights+into+the+Nucleation+by+Employing+a+Step-by-Step+Route%5BTitle%5D)+AND+%22Angewandte+Chemie+International+Edition%22%5BJournal%5D)">Growth Mechanism of Metal–Organic Frameworks: Insights into the Nucleation by Employing a Step-by-Step Route.</a> Angewandte Chemie International Edition. 48 (27), 5038-5041 (2009).</li>
<li>Shekhah, O., Liu, J., Fischer, R. A., Wöll, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((MOF+thin+films%3A+existing+and+future+applications%5BTitle%5D)+AND+%22Chemical+Society+Reviews%22%5BJournal%5D)">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/pubmed?term=((Deposition+of+Metal-Organic+Frameworks+by+Liquid-Phase+Epitaxy%3A+The+Influence+of+Substrate+Functional+Group+Density+on+Film+Orientation%5BTitle%5D)+AND+%22Materials%22%5BJournal%5D)">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/pubmed?term=((Assembly+of+Ultrathin+Polymer+Multilayer+Films+by+Click+Chemistry%5BTitle%5D)+AND+%22Journal+of+the+American+Chemical+Society%22%5BJournal%5D)">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/pubmed?term=((Carbon+Nanomembranes+%28CNMs%29+Supported+by+Polymer%3A+Mechanics+and+Gas+Permeation%5BTitle%5D)+AND+%22Advanced+Materials%22%5BJournal%5D)">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. I. in Functional Metal-Organic Frameworks: Gas Storage, Separation and Catalysis. <a target="_blank" href="http://scholar.google.com/scholar?hl=en&safe=off&q=author%3aJiang%2C+J-X+%22Topics+in+Current+Chemistry.+%28ed+Martin+Schr%C3%B6der%29+Ch%22">Topics in Current Chemistry. (ed Martin Schröder) Ch</a>. 293, Springer. Berlin Heidelberg. 1-33 (2010).</li>
<li>Dawson, R., Cooper, A. I., Adams, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Nanoporous+organic+polymer+networks%5BTitle%5D)+AND+%22Progress+in+Polymer+Science%22%5BJournal%5D)">Nanoporous organic polymer networks.</a> Progress in Polymer Science. 37 (4), 530-563 (2012).</li>
<li>Muller, T., Bräse, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Click+Chemistry+Finds+Its+Way+into+Covalent+Porous+Organic+Materials%5BTitle%5D)+AND+%22Angewandte+Chemie+International+Edition%22%5BJournal%5D)">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. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Covalently+linked+organic+networks%5BTitle%5D)+AND+%22Frontiers+in+Materials%22%5BJournal%5D)">Covalently linked organic networks.</a> Frontiers in Materials. 2, (2015).</li>
<li>Kleinert, M., Winkler, T., Terfort, A., Lindhorst, T. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((A+modular+approach+for+the+construction+and+modification+of+glyco-SAMs+utilizing+1%2C3-dipolar+cycloaddition%5BTitle%5D)+AND+%22Organic+%26+Biomolecular+Chemistry%22%5BJournal%5D)">A modular approach for the construction and modification of glyco-SAMs utilizing 1,3-dipolar cycloaddition.</a> Organic & Biomolecular Chemistry. 6 (12), 2118-2132 (2008).</li>
<li>Plietzsch, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Four-fold+click+reactions%3A+Generation+of+tetrahedral+methane-+and+adamantane-based+building+blocks+for+higher-order+molecular+assemblies%5BTitle%5D)+AND+%22Organic+%26+Biomolecular+Chemistry%22%5BJournal%5D)">Four-fold click reactions: Generation of tetrahedral methane- and adamantane-based building blocks for higher-order molecular assemblies.</a> Organic & Biomolecular Chemistry. 7, (2009).</li>
<li>Greenler, R. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/pubmed?term=((Infrared+Study+of+Adsorbed+Molecules+on+Metal+Surfaces+by+Reflection+Techniques%5BTitle%5D)+AND+%22The+Journal+of+Chemical+Physics%22%5BJournal%5D)">Infrared Study of Adsorbed Molecules on Metal Surfaces by Reflection Techniques.</a> The Journal of Chemical Physics. 44 (1), (1966).</li>
</ol>

The authors have nothing to disclose.

CMP-film oluşturucu sentezi için katalizör çözeltisi taze olarak yer alır. Kırık bir katalizör (örneğin, yükseltgenmiş) çözeltisinin bir mavi rengi ile gösterilir. Taze bir çözüm renksizdir. Bir önemli nokta sıkma kaplama PMMA&#39;nın sonra mika substrat kenarları kesmektir. Ayrıca alt tabaka kusurlar kesilmelidir örneğin, her spot PMMA nedeniyle eksik altın tabakası, mika alt-tabaka ile temas olabilir edildi. Aksi takdirde altın tabakası kolay...

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>Tetrahydrofuran (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&amp;auml;se. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to &lt;sup&gt;9&lt;/sup&gt;.</td></tr><tr><td>1.1.1.1 Methanetetrayltetrakis(4-ethinylenebenzene) (TPM-alkyne)</td><td></td><td></td><td>Provided by AK Prof. Br&amp;auml;se. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to &lt;sup&gt;9&lt;/sup&gt;.</td></tr><tr><td>11-thioacetyl-undecaneacid propargylamide</td><td></td><td></td><td>Provided by AK Prof. Br&amp;auml;se. Institute of organic chemistry, Karlsruhe Institute of Technology. Synthesized according to &lt;sup&gt;8&lt;/sup&gt;.</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 gibi büyük yüzey alanlı malzemeler nedeniyle üstün termal ve kimyasal stabilite ile kombinasyon halinde işlevsel gruplar yüksek değişkenlik ve düşük seviyedeki yoğunluklara kadar, son zamanlarda ilgi giderek artan çekmiştir. Böyle sıkma kaplama gibi genellikle uygulanan teknikler mevcut olmadığından Ancak, çözünmeyen doğa kendi işlenmesinde sorunlara neden olmaktadır. Özellikle CMP ince filmlerin işleme arzu edilir membran uygulamaları için, işleme sorunları ticari uygulama engellemiştir. Burada, moleküler katman-katman (Lbl) sentez yoluyla fonksiyonalize yüzeylerde CMP ince filmlerin ara yüzey sentezini tarif eder. Bu işlem, istenen kalınlığı ve kompozisyon ve daha da arzu edilen bir bileşim eğimlere sahip filmlerin hazırlanması sağlar. Kurban desteklerin kullanımı desteği dağılmasından sonra tarafından müstakil membranların hazırlanması veriyorsentez. Böyle ultra-ince müstakil membranlar işlemek için kurban kaplamalarla koruma Nanomembranlar kopma önlemek için, büyük söz gösterdi. İstenen substrata Nanomembranlar aktarmak için, kaplanmış membranlar hava-sıvı arayüzünde upfloated ve daha sonra daldırma ile kaplama yoluyla transfer edilir.

Membranlar 16 Şekil 4, bir altın gofret transfer CMP-membran IRRA-spektrumlarını göstermektedir kızıl ötesi yansıtma absorpsiyon spektroskopisi (IRRAS). Ile karakterize edilir. Aromatik omurga titreşimlerden tipik bantlar 1605 cm -1, 1515 cm -1 ve 1412 cm -1 altındadır. Reaksiyona girmemiş alkin ve azid grupları 2125 cm -1 ve 1227 cm -1 karakteristik bantlar ile görülebilir. 5 taramalı elektron mikroskobu...

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.

Katman-katman Sentezi ve Müstakil Konjuge mikro gözenekli polimer Nanomembranlar Devri

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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Chemistry

9.3K Görüntüleme.  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.

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

Towards Biomimicking Wood: Fabricated Free-standing Films of Nanocellulose, Lignin, and a Synthetic Polycation

Woody materials are comprised of plant cell walls that contain a layered secondary cell wall composed of structural polymers of polysaccharides and lignin. Layer-by-layer (LbL) assembly process which relies on the assembly of oppositely charged molecules from aqueous solutions was used to build a freestanding composite film of isolated wood polymers of lignin and oxidized nanofibril cellulose (NFC). To facilitate the assembly of these negatively charged polymers, a positively charged polyelectrolyte, poly(diallyldimethylammomium chloride) (PDDA), was used as a linking layer to create this simplified model cell wall. The layered adsorption process was studied quantitatively using quartz crystal microbalance with dissipation monitoring (QCM-D) and ellipsometry. The results showed that layer mass/thickness per adsorbed layer increased as a function of total number of layers. The surface coverage of the adsorbed layers was studied with atomic force microscopy (AFM). Complete coverage of the surface with lignin in all the deposition cycles was found for the system, however, surface coverage by NFC increased with the number of layers. The adsorption process was carried out for 250 cycles (500 bilayers) on a cellulose acetate (CA) substrate. Transparent free-standing LBL assembled nanocomposite films were obtained when the CA substrate was later dissolved in acetone. Scanning electron microscopy (SEM) of the fractured cross-sections showed a lamellar structure, and the thickness per adsorption cycle (PDDA-Lignin-PDDA-NC) was estimated to be 17 nm for two different lignin types used in the study. The data indicates a film with highly controlled architecture where nanocellulose and lignin are spatially deposited on the nanoscale (a polymer-polymer nanocomposites), similar to what is observed in the native cell wall.

The objective of this research was to form synthetic plant cell wall tissue using layer-by-layer assembly of nanocellulose fibrils and isolated lignin assembled from dilute aqueous suspensions.&#160; Surface measurement techniques of quartz crystal microbalance and atomic force microscopy were used to monitor the formation of the polymer-polymer nanocomposite material.

Nanocellulose, Lignin Fabrikasyon Serbest duran Filmler ve Sentetik polikatiyon: Biomimicking Wood Doğru

Woody materials are comprised of plant cell walls that contain a layered secondary cell wall composed of structural polymers of polysaccharides and ...

Kimya

A Technique to Functionalize and Self-assemble Macroscopic Nanoparticle-ligand Monolayer Films onto Template-free Substrates

This protocol describes a self-assembly technique to create macroscopic monolayer films composed of ligand-coated nanoparticles1,2. The simple, robust and scalable technique efficiently functionalizes metallic nanoparticles with thiol-ligands in a miscible water/organic solvent mixture allowing for rapid grafting of thiol groups onto the gold nanoparticle surface. The hydrophobic ligands on the nanoparticles then quickly phase separate the nanoparticles from the aqueous based suspension and confine them to the air-fluid interface. This drives the ligand-capped nanoparticles to form monolayer domains at the air-fluid interface.&#160; The use of water-miscible organic solvents is important as it enables the transport of the nanoparticles from the interface onto template-free substrates.&#160; The flow is mediated by a surface tension gradient3,4 and creates macroscopic, high-density, monolayer nanoparticle-ligand films.&#160; This self-assembly technique may be generalized to include the use of particles of different compositions, size, and shape and may lead to an efficient assembly method to produce low-cost, macroscopic, high-density, monolayer nanoparticle films for wide-spread applications.

A simple, robust and scalable technique to functionalize and self-assemble macroscopic nanoparticle-ligand monolayer films onto template-free substrates is described in this protocol.

Şablon-ücretsiz Substratlarm üzerine makroskobik Nanoparçacık-ligand tabakalı Filmler işlevselleştirmek ve Öz-montajı A Tekniği

This protocol describes a self-assembly technique to create macroscopic monolayer films composed of ligand-coated nanoparticles1,2. The simple, robust and ...

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.

Geniş alanlı Fabrikasyon Ultrathin Polimer Filmler Serbest ayakta

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

Fabrication of the Thermoplastic Microfluidic Channels

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using polymer/nanoparticle composite microscale lysis and solid phase extraction columns. The recovered samples are concentrated, small volume samples that are PCRable, without any additional cleanup. Here, we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then, we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns. We demonstrate grafting and polymerization of a carbon nanotube/polymer composite column for bacterial cell lysis. We then show the lysis process followed by solid phase extraction of nucleic acids from the sample on chip using a silica/polymer composite column. The attached protocols contain detailed instructions on how to make both lysis and solid phase extraction columns.

Here we demonstrate how to fabricate thermoplastic microfluidic chips using hot embossing and heat sealing. Then we demonstrate how to use in situ light directed surface grafting and polymerization through the sealed chip to form the composite solid phase columns.

Termoplastik mikroakışkan Kanallar imalatı

In our lab, we have successfully isolated nucleic acids directly from microliter and submicroliter volumes of human blood, urine and stool using ...

Biyoloji

Formation of Biomembrane Microarrays with a Squeegee-based Assembly Method

Lipid bilayer membranes form the plasma membranes of cells and define the boundaries of subcellular organelles. In nature, these membranes are heterogeneous mixtures of many types of lipids, contain membrane-bound proteins and are decorated with carbohydrates. In some experiments, it is desirable to decouple the biophysical or biochemical properties of the lipid bilayer from those of the natural membrane. Such cases call for the use of model systems such as giant vesicles, liposomes or supported lipid bilayers (SLBs). Arrays of SLBs are particularly attractive for sensing applications and mimicking cell-cell interactions. Here we describe a new method for forming SLB arrays. Submicron-diameter SiO2 beads are first coated with lipid bilayers to form spherical SLBs (SSLBs). The beads are then deposited into an array of micro-fabricated submicron-diameter microwells. The preparation technique uses a "squeegee" to clean the substrate surface, while leaving behind SSLBs that have settled into microwells. This method requires no chemical modification of the microwell substrate, nor any particular targeting ligands on the SSLB. Microwells are occupied by single beads because the well diameter is tuned to be just larger than the bead diameter. Typically, more 75% of the wells are occupied, while the rest remain empty. In buffer SSLB arrays display long-term stability of greater than one week. Multiple types of SSLBs can be placed in a single array by serial deposition, and the arrays can be used for sensing, which we demonstrate by characterizing the interaction of cholera toxin with ganglioside GM1. We also show that phospholipid vesicles without the bead supports and biomembranes from cellular sources can be arrayed with the same method and cell-specific membrane lipids can be identified.

Supported lipid bilayers and natural membrane particles are convenient systems that can approximate the properties of cell membranes and be incorporated in a variety of analytical strategies. Here we demonstrate a method for preparing microarrays composed of supported lipid bilayer-coated SiO2 beads, phospholipid vesicles or natural membrane particles.

Bir Çekçek tabanlı Meclisi Yöntemi ile Biomembrane Mikroarray&#39;ler oluşumu

Lipid bilayer membranes form the plasma membranes of cells and define the boundaries of subcellular organelles. In nature, these membranes are ...

Biyomühendislik

Preparation of Light-responsive Membranes by a Combined Surface Grafting and Postmodification Process

In order to modify the surface tension of commercial available track-edged polymer membranes, a procedure of surface-initiated polymerization is presented. The polymerization from the membrane surface is induced by plasma treatment of the membrane, followed by reacting the membrane surface with a methanolic solution of 2-hydroxyethyl methacrylate (HEMA). Special attention is given to the process parameters for the plasma treatment prior to the polymerization on the surface. For example, the influence of the plasma-treatment on different types of membranes (e.g.&#160;polyester, polycarbonate, polyvinylidene fluoride) is studied. Furthermore, the time-dependent stability of the surface-grafted membranes is shown by contact angle measurements. When grafting poly(2-hydroxyethyl methacrylate) (PHEMA) in this way, the surface can be further modified by esterification of the alcohol moiety of the polymer with a carboxylic acid function of the desired substance. These reactions can therefore be used for the functionalization of the membrane surface. For example, the surface tension of the membrane can be changed or a desired functionality as the presented light-responsiveness can be inserted. This is demonstrated by reacting PHEMA with a carboxylic acid functionalized spirobenzopyran unit which leads to a light-responsive membrane. The choice of solvent plays a major role in the postmodification step and is discussed in more detail in this paper. The permeability measurements of such functionalized membranes are performed using a Franz cell with an external light source. By changing the wavelength of the light from the visible to the UV-range, a change of permeability of aqueous caffeine solutions is observed.

A plasma-induced polymerization procedure is described for the surface-initiated polymerization on polymer membranes. Further postmodification of the grafted polymer with photochromic substances is presented with a protocol of conducting permeability measurements of light-responsive membranes.

Bir Kombine Yüzey Tırnak ve Postmodification Süreci Işık duyarlı Membranların Hazırlanması

In order to modify the surface tension of commercial available track-edged polymer membranes, a procedure of surface-initiated polymerization is ...

Fabricating Reactive Surfaces with Brush-like and Crosslinked Films of Azlactone-Functionalized Block Co-Polymers

In this paper, fabrication methods that generate novel surfaces using the azlactone-based block co-polymer, poly (glycidyl methacrylate)-block-poly (vinyl dimethyl azlactone) (PGMA-b-PVDMA), are presented. Due to the high reactivity of azlactone groups towards amine, thiol, and hydroxyl groups, PGMA-b-PVDMA surfaces can be modified with secondary molecules to create chemically or biologically functionalized interfaces for a variety of applications. Previous reports of patterned PGMA-b-PVDMA interfaces have used traditional top-down patterning techniques that generate non-uniform films and poorly controlled background chemistries. Here, we describe customized patterning techniques that enable precise deposition of highly uniform PGMA-b-PVDMA films in backgrounds that are chemically inert or that have biomolecule-repellent properties. Importantly, these methods are designed to deposit PGMA-b-PVDMA films in a manner that completely preserves azlactone functionality through each processing step. Patterned films show well-controlled thicknesses that correspond to polymer brushes (~90 nm) or to highly crosslinked structures (~1-10 &#956;m). Brush patterns are generated using either the parylene lift-off or interface directed assembly methods described and are useful for precise modulation of overall chemical surface reactivity by adjusting either the PGMA-b-PVDMA pattern density or the length of the VDMA block. In contrast, the thick, crosslinked PGMA-b-PVDMA patterns are obtained using a customized micro-contact printing technique and offer the benefit of higher loading or capture of secondary material due to higher surface area to volume ratios. Detailed experimental steps, critical film characterizations, and trouble-shooting guides for each fabrication method are discussed.

Surface fabrication methods for patterned deposition of nanometer thick brushes or micron thick, crosslinked films of an azlactone block co-polymer are reported. Critical experimental steps, representative results, and limitations of each method are discussed. These methods are useful for creating functional interfaces with tailored physical features and tunable surface reactivity.

Fırça benzeri ile reaktif yüzeyler imalatı ve Azlactone Functionalized blok ortak polimerler çapraz filmleri

In this paper, fabrication methods that generate novel surfaces using the azlactone-based block co-polymer, poly (glycidyl methacrylate)-block-poly (vinyl ...

Mühendislik

Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes

We report the synthesis of thin, highly intergrown, polycrystalline metal-organic framework (MOF) membranes on a wide range of unmodified porous and non-porous supports (polymer, ceramic, metal, carbon, and graphene). We developed a novel crystallization technique, which is termed the ENACT approach: the electrophoretic nuclei assembly for the crystallization of highly intergrown thin films (ENACT). This approach allows for a high density of heterogeneous nucleation of MOFs on a chosen substrate via the electrophoretic deposition (EPD) directly from the precursor sol. The growth of well-packed MOF nuclei leads to a highly intergrown polycrystalline MOF film. We show that this simple approach can be used for the synthesis of thin, intergrown zeolite imidazole framework (ZIF)-7 and ZIF-8 films. The resulting 500 nm-thick ZIF-8 membranes show a considerably high H2 permeance (8.3 x 10-6 mol m-2 s-1 Pa-1) and ideal gas selectivities (7.3 for H2/CO2, 15.5 for H2/N2, 16.2 for H2/CH4, and 2655 for H2/C3H8). An attractive performance for C3H6/C3H8 separation is also achieved (a C3H6 permeance of 9.9 x 10-8 mol m-2 s-1 Pa-1 and a C3H6/C3H8 ideal selectivity of 31.6 at 25 &#176;C). Overall, the ENACT process, owing to its simplicity, can be extended to synthesize intergrown thin films of a wide range of nanoporous crystalline materials.

A simple, reproducible, and versatile approach for the synthesis of intergrown, polycrystalline metal-organic framework membranes on a wide range of unmodified porous and non-porous supports is presented.

Elektroforetik kristalizasyon Ultrathin yüksek performanslı Metal organik Framework membranlar

We report the synthesis of thin, highly intergrown, polycrystalline metal-organic framework (MOF) membranes on a wide range of unmodified porous and ...

Procedure for the Transfer of Polymer Films Onto Porous Substrates with Minimized Defects

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support substrates. Accomplishing this transfer in a highly controlled, mechanized, and reproducible manner can eliminate the creation of macroscale defect structures (e.g., tears, cracks, and wrinkles) within the thin film that compromise device performance and the usable area per sample. Here, we describe a general protocol for the highly controlled and mechanized transfer of a polymeric thin film onto an arbitrary porous support substrate for eventual use as a water filtration membrane device. Specifically, we fabricate a block copolymer (BCP) thin film on top of a sacrificial, water-soluble poly(acrylic acid) (PAA) layer and silicon wafer substrate. We then utilize a custom-designed, 3D-printed transfer tool and drain chamber system to deposit, lift-off, and transfer the BCP thin film onto the center of a porous anodized aluminum oxide (AAO) support disc. The transferred BCP thin film is shown to be consistently placed onto the center of the support surface due to the guidance of the meniscus formed between the water and the 3D-printed plastic drain chamber. We also compare our mechanized transfer-processed thin films to those that have been transferred by hand with the use of tweezers. Optical inspection and image analysis of the transferred thin films from the mechanized process confirm that little-to-no macroscale inhomogeneities or plastic deformations are produced, as compared to the multitude of tears and wrinkles produced from manual transfer by hand. Our results suggest that the proposed strategy for thin film transfer can reduce defects when compared to other methods across many systems and applications.

We present a procedure for highly controlled and wrinkle-free transfer of block copolymer thin films onto porous support substrates using a 3D-printed drain chamber. The drain chamber design is of general relevance to all procedures involving transfer of macromolecular films onto porous substrates, which is normally done by hand in an irreproducible fashion.

Polimer filmlerin küçültülmüş kusurlarla gözenekli substratlar üzerine aktarımı için prosedür

The fabrication of devices containing thin film composite membranes necessitates the transfer of these films onto the surfaces of arbitrary support ...

Microscopic Visualization of Porous Nanographenes Synthesized through a Combination of Solution and On-Surface Chemistry

On-surface synthesis has recently been regarded as a promising approach for the generation of new molecular structures. It has been particularly successful in the synthesis of graphene nanoribbons, nanographenes and intrinsically reactive and instable, yet attractive species. It is based on the combination of solution chemistry aimed at preparation of appropriate molecular precursors for further ultra-high vacuum surface assisted transformations. This approach also owes its success to an incredible development of characterization techniques, such as scanning tunneling/atomic force microscopy and related methods, which allow detailed, local characterization at atomic scale. While the surface-assisted synthesis can provide molecular nanostructures with outstanding precision, down to single atoms, it suffers from basing on metallic surfaces and often limited yield. Therefore, the extension of the approach away from metals and the struggle to increase productivity seem to be significant challenges toward wider applications. Herein, we demonstrate the on-surface synthesis approach for generation of non-planar nanographenes, which are synthesized through a combination of solution chemistry and sequential surface-assisted processes, together with the detailed characterization by scanning probe microscopy methods.

<meta charset="utf8"></head><body>Çözelti ve Yüzey Kimyası Kombinasyonu ile Sentezlenen Gözenekli Nanografenlerin Mikroskobik Görüntülenmesi

A combination of solution and surface assisted synthesis opens new directions in the atomically precise synthesis of nanostructures. Scanning tunneling microscopy (STM) supplemented by non-contact atomic force microscopy (nc-AFM) enables detailed characterization of newly designed and generated carbon-based nano-objects.

Katman-katman Sentezi ve Müstakil Konjuge mikro gözenekli polimer Nanomembranlar Devri

Özet

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