层 - 层的合成和独立式共轭微孔聚合物纳米薄膜的转移

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作为大表面积材料已经引起了近来越来越大的兴趣，由于它们的高变异性的官能团的组合掺入其优异的热和化学稳定性，和低的密度。然而，它们的不溶性质会产生问题在它们的处理，因为，如旋涂通常适用技术是不可用的。特别是对于膜应用，其中CMP为薄膜的处理是可取的，则处理问题阻碍他们的商业应用。

这里，我们描述在通过分子层 – 层（LBL）合成官能化基底的CMP薄膜的界面合成。此过程允许具有所需厚度和组成，甚至所需组成梯度的薄膜的制备。

使用牺牲载体允许通过后溶解载体的独立式膜的制备的合成。为了处理这种超薄独立的膜与牺牲涂料的保护表现出极大的承诺，避免了纳米薄膜破裂。到的纳米薄膜转移到期望的基材，所述涂覆的膜upfloated在空气 – 液体界面，然后通过浸涂传送。

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

1.合成的CMP薄膜通过顺序加入金云母自组装单层（SAM）官能化。 制备11-硫代乙酰基十一烷酸炔丙基酰胺14在乙醇1mM的溶液（SAM-溶液）。混合使用超声波浴，直到解决方案是明确的。用铝箔避光的瓶子。 获取在氩气中金云母片。从储存容器撤走后直接浸入云母晶片18小时在SAM的溶液。 取所制备的Au-云母晶片出SAM-溶液，冲洗，在氮气流下乙醇和干燥。之后存?…

Representative Results

膜的特征在于红外反射吸收光谱（IRRAS）。16 图4示出 IRRA谱从在CMP膜转移至金晶片。由芳族骨架的振动典型峰是一千六百○五-1，一千五百十五-1和1412厘米-1。未反应的炔和叠氮基团可通过特征频带在2125厘米-1和一二二七-1可以观察到。 图5显示的扫描电子显微镜（SEM）图像。的独立式膜是清晰可见。 <p class="jove_content" fo:…

Discussion

对于在CMP-膜的合成催化剂的溶液必须是新鲜。破碎的催化剂（即，氧化的）由溶液的蓝色着色指示。新鲜的溶液是无色的。

一个关键点是旋涂PMMA后裁切云母基材的边缘。另外在基板的缺陷应该削减， 即，每个点是聚甲基丙烯酸甲酯可以来缺失金层，因为在与云母基板接触。否则金层不能从云母基板容易剥离。另外关于金层的云母基材支队，支队开始在?…

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