我们没有致谢

注意: 在使用前请先戴上实验室大衣、手套和安全眼镜, 并阅读材料安全数据表 (MSDS)。所有购买的材料都已使用, 无需进一步提纯。
1. 制备由苯乙烯/PFO/水溶液混合液组成的乳液
<ol><li>为制备5毫米的水 sds 溶液, 在高纯度 H2O 10 毫升中溶解14.5 毫克 sds。 注: 高纯度 H2O 已被使用 (电阻率 (R) = 18 ω cm, 表面张力 (γ) = 72.0 mN m-1在25° c)。</li>
	<li>加入1.5 克苯乙烯, 0.6 克 PFO, 0.9 克5毫米的水溶液 SDS 溶液到10毫升玻璃小瓶与搅拌棒。 注: 在扫描共聚焦荧光显微镜观察, 添加2.6 毫克香豆素102和0.062 毫克的素的混合物。</li>
	<li>在室温下搅动60分钟 1150 rpm 的混合物, 然后将温度升高到80° c。</li>
	<li>搅拌的混合物为60分钟, 在 1150 rpm 和80° c。</li>
</ol>2. 用苯乙烯/PFO/水溶液混合物组成的乳液制备聚合物微粒
<ol><li>添加3.9 毫克的钾硫酸钾, 2 毫克的芘, 1.5 克苯乙烯, 0.6 克 PFO, 0.9 克5毫米的水溶液 SDS 溶液到10毫升玻璃小瓶与搅拌棒和密封它与橡胶隔膜。</li>
	<li>通过注射器针将氮气 Deoxygenate 30 分钟。 注意: 缓慢流动的氮气不会产生大量的泡沫。</li>
	<li>准备乳液, 搅拌60分钟的混合物在 1150 rpm 和室温, 然后提高温度到80° c。</li>
	<li>搅拌的混合物为30分钟, 在 1150 rpm 和80° c。</li>
	<li>将所产生的溶液 (3 毫升) 中的多云部分 (1.8 毫升) 转移到试管中, 然后加入30% 乙醇溶液以完全终止聚合反应。</li>
	<li>几种 (功率: 130 W, 频率: 4.2 赫), 10 分钟洗涤产生的聚合物粒子, 然后离心10分钟, 在 2300 x g。</li>
	<li>要获得聚合物粒子, 从试管中除去上清溶液。</li>
	<li>在试管中加入3毫升的水到所产生的固体中。几种 (功率: 130 W, 频率: 4.2 赫) 为10分钟和离心机为 10 min 在 2300 x g. 从试管中取出上清液。</li>
	<li>重复洗涤过程 (步骤 2.8), 直到没有从上清溶液生成泡沫。蒸发水获得固体的空心高分子颗粒。</li>
</ol>3. 利用空心高分子微粒制备微胶囊
<ol><li>加入1毫克的空心聚苯乙烯颗粒 (步骤 2.9) 和4毫升的水到一个10毫升玻璃小瓶与搅拌棒。</li>
	<li>几种 (功率: 130 W, 频率: 4.2 赫), 用于在水中分散空心粒子10分钟。</li>
	<li>在室温下, 将0.1 毫升的甲苯添加到水中分散的颗粒, 然后搅拌1小时 100 rpm。将液体转移到试管。 注意: 如果每分钟的自转增加, 粒子的形态就会变形。</li>
	<li>离心液体为10分钟在 2300 x g 分离微囊形成它。从试管中取出上清液。</li>
</ol>

<ol>
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A., Chang, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Microfluidic-Assisted+Synthesis+of+Polymer+Particles.">Microfluidic-Assisted Synthesis of Polymer Particles.</a> Chem Eng Tech. 31 (8), 1099-1115 (2008).</li><li>Higuchi, T., Yabu, H., Shimomura, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simple+preparation+of+hemispherical+polystyrene+particles.">Simple preparation of hemispherical polystyrene particles.</a> Colloids Surf A. 284, 250-253 (2006).</li><li>Sun, Z. Q., 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=Nonspherical+Colloidal+Crystals+Fabricated+by+the+Thermal+Pressing+of+Colloidal+Crystal+Chips.">Nonspherical Colloidal Crystals Fabricated by the Thermal Pressing of Colloidal Crystal Chips.</a> Langmuir. 21 (20), 8987-8991 (2005).</li><li>Deng, Y., 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=A+novel+approach+to+the+construction+of+3-D+ordered+macrostructures+with+polyhedral+particles.">A novel approach to the construction of 3-D ordered macrostructures with polyhedral particles.</a> J Mater Chem. 18 (4), 408-415 (2008).</li><li>Hyuk Im, S., Jeong, U., Xia, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polymer+hollow+particles+with+controllable+holes+in+their+surfaces.">Polymer hollow particles with controllable holes in their surfaces.</a> Nat Mater. 4 (9), 671-675 (2005).</li><li>Saito, N., Kagari, Y., Okubo, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Effect+of+Colloidal+Stabilizer+on+the+Shape+of+Polystyrene/Poly(methyl+methacrylate)+Composite+Particles+Prepared+in+Aqueous+Medium+by+the+Solvent+Evaporation+Method.">Effect of Colloidal Stabilizer on the Shape of Polystyrene/Poly(methyl methacrylate) Composite Particles Prepared in Aqueous Medium by the Solvent Evaporation Method.</a> Langmuir. 22 (22), 9397-9402 (2006).</li><li>Cai, P. -. j., Tang, Y. -. j., Wang, Y. -. t., Cao, Y. -. j. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+of+polystyrene+hollow+spheres+in+W/O/W+multiple+emulsions.">Fabrication of polystyrene hollow spheres in W/O/W multiple emulsions.</a> Mater Chem Phys. 124 (1), 10-12 (2010).</li><li>Liang, S. -. 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我们没有什么要透露的。

在水 SDS 浓度和苯乙烯、PFO 的重量分数的 10% 以上, 得到了含苯乙烯和 PFO 的乳液。当含有该液滴的乳液的各种重量分数被聚合为30分钟时, 可以获得所有成分的空心聚苯乙烯颗粒。这些结果表明, 此处所示的协议很简单。此外, 本文所述方法中的聚合时间可以控制空心聚苯乙烯颗粒的直径、孔径大小和孔体积。
我们建议以下的机制来制造空心聚苯乙烯颗粒。在80° c 的含水 SDS 溶液、苯乙烯和 PFO 混合物的 O/W 乳液中形成了由苯乙烯和 PFO 组成的两面油滴。PFO 液滴位于苯乙烯滴的表面。由于作为聚合的引发剂的科索沃警察部队在水相中是可溶的, 聚合将在苯乙烯/水溶液 SDS 溶液的界面上进行。在80° c 时, 三元乳液中苯乙烯聚合成聚苯乙烯, 而 PFO 没有聚合基团, 在该温度下仍留在乳液中。聚合终止后, 通过去除 PFO, 形成聚苯乙烯颗粒上的孔。因此, 在表面上有孔的中空杯状聚苯乙烯颗粒是任何苯乙烯和 PFO 的重量分数和所有聚合时间的产物。
在90分钟内, 将少量的甲苯加入到由自由基聚合制备的空心聚苯乙烯颗粒上, 就会使空心聚苯乙烯颗粒上的孔洞得到密封。这一现象与赫 al.9报告的是一致的。封装法可以在微粒中含有水的物质。
在本文中, 我们展示了一种使用由苯乙烯和 PFO 组成的含油滴的中空聚合物颗粒的制备方法, 它们是相互不相容的。非球形高分子颗粒的制备方法, 由于其在各种应用中的潜在用途, 已经得到了广泛的研究。该策略采用烃油和氟碳油的两面油滴, 适用于不同类型单体和药物输送系统的非球形聚合物颗粒的制备。

虽然球形高分子颗粒已广泛应用于各种工业应用, 但众所周知, 酒窝粒子, 半球, 磁盘, 和椭球, 已准备通过播种聚合1,2,3, 使用具有特定几何形状的微的非球形单体液滴的光聚合,4,5, 使用聚合物再的自组织6, 以及球形聚合物的变形微粒由机械外部力量7,8。特别是, 由溶剂9,10 , 用多乳剂聚合而成的球形高分子颗粒的好溶剂蒸发制备了微米级的中空聚合物颗粒。11,12。
在这项工作中, 我们关注的是烃类和氟碳油的相互溶在聚合物微粒的制造中的应用。混合表面活性剂在分子中有一个碳氢化合物链和一个氟碳链。此前, 我们报告了在常规表面活性剂中未观察到的混合表面活性剂的独特特性13,14,15。我们还研究了使用烃类油、氟碳油和表面活性剂溶液的乳液, 它们是相互不相容的16。然而, 对乳剂的研究很少有17。这些研究描述了由烃油和氟碳油组成的油滴在表面活性剂溶液中的形貌。
在这里, 我们展示了一个详细的协议制造空心聚合物颗粒的基础聚合使用油滴的乳液由烃油, 氟碳油, 和水钠硫酸钠 (SDS) 溶液。本文提出了一种新的非球形高分子颗粒制备方法, 它有别于常规的工艺。该方法能在短时间内简单地制备空心高分子颗粒。此外, 还显示了通过空心高分子微粒制备微胶囊的协议。

<table>
	<tbody>
		<tr>
			<td>Material</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium dodecylsulfate, 95.0%</td>
			<td>Wako Pure Chemical Industries, Ltd.</td>
			<td>192-08672</td>
			<td></td>
		</tr>
		<tr>
			<td>Styrene, 99.0%</td>
			<td>Tokyo Chemical Industry Co. Ltd.</td>
			<td>S0095</td>
			<td></td>
		</tr>
		<tr>
			<td>Perfluorooctane, 99%</td>
			<td>Fluorochem Ltd.</td>
			<td>8706</td>
			<td></td>
		</tr>
		<tr>
			<td>Coumarin 102, 97.0%</td>
			<td>Tokyo Chemical Industry Co. Ltd.</td>
			<td>C2267</td>
			<td></td>
		</tr>
		<tr>
			<td>Calcein</td>
			<td>Dojindo Molecular Technologies, Inc.</td>
			<td>C001</td>
			<td></td>
		</tr>
		<tr>
			<td>Potassium peroxodisulfate, 98.0%</td>
			<td>Kanto Chemical Co., Inc.</td>
			<td>32375-30</td>
			<td></td>
		</tr>
		<tr>
			<td>Pyrene, 97.0%</td>
			<td>Wako Pure Chemical Industries, Ltd.</td>
			<td>167-05302</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol, 99.5%</td>
			<td>Kanto Chemical Co., Inc.</td>
			<td>14033-00</td>
			<td></td>
		</tr>
		<tr>
			<td>Toluene, 99.5%</td>
			<td>Kanto Chemical Co., Inc.</td>
			<td>40180-00</td>
			<td></td>
		</tr>
		<tr>
			<td>Name</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Equipment</td>
			<td></td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Scanning Electron Microscope</td>
			<td>Hitachi High-Technologies Corporation</td>
			<td>S-4800</td>
			<td></td>
		</tr>
		<tr>
			<td>Scanning Transmission Electron Microscope</td>
			<td>Hitachi High-Technologies Corporation</td>
			<td>S-4800</td>
			<td></td>
		</tr>
		<tr>
			<td>Ultrasonic cleaner</td>
			<td>Branson Ultrasonics, Emerson Japan, Ltd.</td>
			<td>Model 3510</td>
			<td></td>
		</tr>
		<tr>
			<td>Centrifuge</td>
			<td>AS ONE Corporation</td>
			<td>CN-1050</td>
			<td></td>
		</tr>
	</tbody>
</table>

preparation of hollow polystyrene particles and microcapsules by radical polymerization of janus droplets consisting of hydrocarbon and fluorocarbon oils

在这篇文章中, 我们已经演示了一种方法, 生产空心颗粒和微胶囊使用油滴由烃油 (苯乙烯) 和氟碳油 (氟-n-辛烷, PFO) 在水表面活性剂 (钠硫酸钠,SDS) 解决方案。由于氟碳油与烃类油不相容, 这两种油分离。乳液是由搅拌苯乙烯/PFO/水 SDS 溶液混合物在80° c。用光学显微镜和扫描共聚焦荧光显微镜观察了乳液的类型和液滴的形貌。结果表明, 在 SDS 溶液中形成了由相互不相容的苯乙烯和 PFO 组成的油滴。聚苯乙烯颗粒是由苯乙烯/PFO/水 SDS 溶液在80° c 的三元混合物的自由基聚合制备的。通过扫描电子显微镜和扫描透射电镜观察, 证实了聚苯乙烯的形貌。这些观察表明, 表面上有一个孔的聚苯乙烯空心颗粒的制备。根据我们的知识, 这种方法是一种新的战略使用溶烃和氟碳油。空心颗粒也可用于微胶囊的制备。

光和扫描共聚焦荧光显微镜观察, 以确定的形态和组成的液滴在乳液由苯乙烯, PFO, 和5毫米水溶液 SDS (图 1)。扫描电子显微镜 (SEM) 和扫描透射电镜 (词干) 观察显示空心粒子和微胶囊的形成 (图 2)。
由苯乙烯/PFO/水 sds 溶液三元混合物组成的乳剂的 DIC 和共聚焦荧光显微图像表明, 连续相是水 sds 溶液, 因为在素中观察到的绿色荧光连续相, 因此, 油内水型乳剂形成 (图 1a和1b)。这些图像还表明, 油滴包括苯乙烯和 PFO, 这是相互不相容的。含香豆素102乳剂的 DIC 和共焦荧光显微图像显示, PFO 液滴位于水与苯乙烯滴之间的界面上。苯乙烯、PFO 和水 SDS 溶液的三元混合物, 其5毫米的乳液含有由苯乙烯和 PFO 组成的两面油滴。
styrene/PFO/5 毫米水溶液的乳液自由基聚合制备的聚合物粒子的扫描电镜和干图表明, 表面有孔的空心非球形聚苯乙烯颗粒 (图 2a和2b). 通过扫描电镜和茎秆观察200粒子, 评价空心聚苯乙烯颗粒的形成速率、直径和孔径。平均直径估计从 SEM 观察是1.3 µm。尺寸与由动态光散射测量估计的聚合物颗粒的直径一致。形成率约为100%。空心颗粒中孔的平均孔径和体积分别为0.8 ±0.4 µm 和0.9 ±0.4 µm3。因此, 在乳液中含有苯乙烯的同液滴的自由基聚合, 制备出具有0.8 µm 孔的空心聚苯乙烯颗粒。
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/56922/56922fig1.jpg"> 图1。由苯乙烯、PFO 和5毫米水溶液 SDS 溶液组成的乳液中的液滴形态.(a)差分干扰对比 (DIC) 和(b)共焦荧光显微图像的乳液含有水荧光素。(c) DIC 和(d)含有油溶性荧光香豆素102的乳剂的共焦荧光显微图像。<a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56922/56922fig1large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/56922/56922fig2.jpg"> 图2。采用苯乙烯、PFO 和5毫米水溶液 SDS 的乳液组成的空心聚苯乙烯颗粒和微胶囊的形貌。(a) SEM 和(b)空心聚苯乙烯颗粒的茎图像。(c) SEM 和(d)微胶囊的茎图像。<a href="//cloudflare-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/56922/56922fig2large.jpg" target="_blank">请单击此处查看此图的较大版本.</a>

Watch this Scientific Journal Video about Preparation of Hollow Polystyrene Particles and Microcapsules by Radical Polymerization of Janus Droplets Consisting of Hydrocarbon and Fluorocarbon Oils at J

Preparation of Hollow Polystyrene Particles and Microcapsules by Radical Polymerization of Janus Droplets Consisting of Hydrocarbon and Fluorocarbon Oils

由烃类和氟碳油组成的同液滴的自由基聚合制备空心聚苯乙烯颗粒和微胶囊

介绍了用苯乙烯、氟-n-辛烷和水溶液 SDS (硫酸钠) 溶液制备空心高分子颗粒和微胶囊的方法。

In this article, we have demonstrated a method for producing hollow particles and microcapsules using oil droplets consisting of hydrocarbon oil (styrene) ...

preparation-hollow-polystyrene-particles-microcapsules-radical

Research

JoVE Journal

Chemistry

9.9K 次观看.  Tokyo University of Science. 介绍了用苯乙烯、氟-n-辛烷和水溶液 SDS (硫酸钠) 溶液制备空心高分子颗粒和微胶囊的方法。

视频: Preparation of Hollow Polystyrene Particles and Microcapsules by Radical Polymerization of Janus Droplets Consisting of Hydrocarbon and Fluorocarbon Oils

Origami Inspired Self-assembly of Patterned and Reconfigurable Particles

There are numerous techniques such as photolithography, electron-beam lithography and soft-lithography that can be used to precisely pattern two dimensional (2D) structures. These technologies are mature, offer high precision and many of them can be implemented in a high-throughput manner. We leverage the advantages of planar lithography and combine them with self-folding methods1-20 wherein physical forces derived from surface tension or residual stress, are used to curve or fold planar structures into three dimensional (3D) structures. In doing so, we make it possible to mass produce precisely patterned static and reconfigurable particles that are challenging to synthesize.
In this paper, we detail visualized experimental protocols to create patterned particles, notably, (a) permanently bonded, hollow, polyhedra that self-assemble and self-seal due to the minimization of surface energy of liquefied hinges21-23 and (b) grippers that self-fold due to residual stress powered hinges24,25. The specific protocol described can be used to create particles with overall sizes ranging from the micrometer to the centimeter length scales. Further, arbitrary patterns can be defined on the surfaces of the particles of importance in colloidal science, electronics, optics and medicine. More generally, the concept of self-assembling mechanically rigid particles with self-sealing hinges is applicable, with some process modifications, to the creation of particles at even smaller, 100 nm length scales22, 26 and with a range of materials including metals21, semiconductors9 and polymers27. With respect to residual stress powered actuation of reconfigurable grasping devices, our specific protocol utilizes chromium hinges of relevance to devices with sizes ranging from 100 &mu;m to 2.5 mm. However, more generally, the concept of such tether-free residual stress powered actuation can be used with alternate high-stress materials such as heteroepitaxially deposited semiconductor films5,7 to possibly create even smaller nanoscale grasping devices.

We describe experimental details of the synthesis of patterned and reconfigurable particles from two dimensional (2D) precursors. This methodology can be used to create particles in a variety of shapes including polyhedra and grasping devices at length scales ranging from the micro to centimeter scale.

折纸灵感的图案和可重构颗粒自组装

There are numerous techniques such as photolithography, electron-beam lithography and soft-lithography that can be used to precisely pattern two ...

科研

化学

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow

While the first Electron Paramagnetic Resonance (EPR) studies regarding the effects of oxidation on the structure and stability of carbon radicals date back to the early 1980s the focus of these early papers primarily characterized the changes to the structures under extremely harsh conditions (pH or temperature)1-3. It is also known that paramagnetic molecular oxygen undergoes a Heisenberg spin exchange interaction with stable radicals that extremely broadens the EPR signal4-6. Recently, we reported interesting results where this interaction of molecular oxygen with a certain part of the existing stable radical structure can be reversibly affected simply by flowing a diamagnetic gas through the carbon samples at STP7. As flows of He, CO2, and N2 had a similar effect these interactions occur at the surface area of the macropore system.
This manuscript highlights the experimental techniques, work-up, and analysis towards affecting the existing stable radical nature in the carbon structures. It is hoped that it will help towards further development and understanding of these interactions in the community at large.

Stable radicals that are present in carbon substrates interact with paramagnetic oxygen through a Heisenberg spin exchange. This interaction can be significantly reduced under STP conditions by flowing a diamagnetic gas over the carbon system. This manuscript describes a simple method to characterize the nature of those radicals.

通过电子顺磁共振和校准气体流量探索碳表面的激进性质

While the first Electron Paramagnetic Resonance (EPR) studies regarding the effects of oxidation on the structure and stability of carbon radicals date ...

Facile and Efficient Preparation of Tri-component Fluorescent Glycopolymers via RAFT-controlled Polymerization

Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and efficient synthesis of well-controlled fluorescent statistical glycopolymers using reversible addition-fragmentation chain-transfer (RAFT)-based polymerization is demonstrated. The synthesis starts with the preparation of &#946;-galactose-containing glycomonomer 2-lactobionamidoethyl methacrylamide obtained by reaction of lactobionolactone and N-(2-aminoethyl) methacrylamide (AEMA). 2-Gluconamidoethyl methacrylamide (GAEMA) is used as a structural analog lacking a terminal &#946;-galactoside. The following RAFT-mediated copolymerization reaction involves three different monomers: N-(2-hydroxyethyl) acrylamide as spacer, AEMA as target for further fluorescence labeling, and the glycomonomers. Tolerant of aqueous systems, the RAFT agent used in the reaction is (4-cyanopentanoic acid)-4-dithiobenzoate. Low dispersities (&#8804;1.32), predictable copolymer compositions, and high reproducibility of the polymerizations were observed among the products. Fluorescent polymers are obtained by modifying the glycopolymers with carboxyfluorescein succinimidyl ester targeting the primary amine functional groups on AEMA. Lectin-binding specificities of the resulting glycopolymers are verified by testing with corresponding agarose beads coated with specific glycoepitope recognizing lectins. Because of the ease of the synthesis, the tight control of the product compositions and the good reproducibility of the reaction, this protocol can be translated towards preparation of other RAFT-based glycopolymers with specific structures and compositions, as desired.

An efficient, three-step synthesis of RAFT-based fluorescent glycopolymers, consisting of glycomonomer preparation, copolymerization, and post-modification, is demonstrated. This protocol can be used to prepare RAFT-based statistical glycopolymers with desired structures.

通过RAFT控制聚合轻便和高效制备三组分荧光Glycopolymers

Synthetic glycopolymers are instrumental and versatile tools used in various biochemical and biomedical research fields. An example of a facile and ...

Using Polystyrene-block-poly(acrylic acid)-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization

We present a template-free method for &#8220;polymerizing&#8221; nanoparticles into long chains without side branches. A variety of nanoparticles are encapsulated in polystyrene-block-poly(acrylic acid) (PSPAA) shells and then used as monomers for their self-assembly. Spherical PSPAA micelles upon acid treatment are known to assemble into cylindrical micelles. Exploiting this tendency, the core-shell nanoparticles are induced to aggregate, coalesce, and then transform into long chains. When more than one type of nanoparticles are used, random and block &#8220;copolymers&#8221; of nanoparticles can be obtained. Detailed procedures are reported for the PSPAA encapsulation of nanoparticles, homo- and co-polymerization of the core-shell nanoparticles, separation and purification of the resulting nanoparticle chains. Transformations of single-line chains into double- and triple-line chains are also presented. The synergy between the polymer shell and the embedded nanoparticles leads to an unusual chain-growth polymerization mode, giving long nanoparticle chains that are distinct from the products of the traditional step-growth aggregation process.

Using Polystyrene-block-polyacrylic acid-coated Metal Nanoparticles as Monomers for Their Homo- and Co-polymerization

We report protocols for &#8220;polymerizing&#8221; various types of polymer-encapsulated metal nanoparticles into long chains of &#8220;homo-&#8220; and &#8220;co-polymers&#8221;.

使用聚苯乙烯<em&gt;块</em&gt; - 聚（丙烯酸）涂层的金属纳米颗粒作为单体他们均聚物和共聚物聚合

We present a template-free method for &#8220;polymerizing&#8221; nanoparticles into long chains without side branches. A variety of nanoparticles are ...

Facile Preparation of Internally Self-assembled Lipid Particles Stabilized by Carbon Nanotubes

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled (functionalized) CNTs are used as stabilizers to produce Pickering type oil-in-water (O/W) emulsions. Lipids namely, Dimodan U and Phytantriol are used as emulsifiers, which in excess water self-assemble into the bicontinuous cubic Pn3m phase. This highly viscous phase is fragmented into smaller particles using a probe ultrasonicator in presence of conventional surfactant stabilizers or CNTs as done here. Initially, the CNTs (powder form) are dispersed in water followed by further ultrasonication with the molten lipid to form the final emulsion. During this process the CNTs get coated with lipid molecules, which in turn are presumed to surround the lipid droplets to form a particulate emulsion that is stable for months. The average size of CNT-stabilized nanostructured lipid particles is in the submicron range, which compares well with the particles stabilized using conventional surfactants. Small angle X-ray scattering data confirms the retention of the original Pn3m cubic phase in the CNT-stabilized lipid dispersions as compared to the pure lipid phase (bulk state). Blue shift and lowering of the intensities in characteristic G and G&#39; bands of CNTs observed in Raman spectroscopy characterize the interaction between CNT surface and lipid molecules. These results suggest that the interactions between the CNTs and lipids are responsible for their mutual stabilization in aqueous solutions. As the concentrations of CNTs employed for stabilization are very low and lipid molecules are able to functionalize the CNTs, the toxicity of CNTs is expected to be insignificant while their biocompatibility is greatly enhanced. Hence the present approach finds a great potential in various biomedical applications, for instance, for developing hybrid nanocarrier systems for the delivery of multiple functional molecules as in combination therapy or polytherapy.

We report on a smart application of carbon nanotubes for kinetic stabilization of lipid particles that contain self-assembled nanostructures in their cores. The preparation of lipid particles requires rather low concentrations of carbon nanotubes permitting their use in biomedical applications such as drug delivery.

内部自组装脂质颗粒的简易制备碳纳米管稳定

We present a facile method to prepare nanostructured lipid particles stabilized by carbon nanotubes (CNTs). Single-walled (pristine) and multi-walled ...

Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst

A standardized technique for atom transfer radical polymerization of vinyl monomers using perylene as a visible-light photocatalyst is presented. The procedure is performed under an inert atmosphere using air- and water-exclusion techniques. The outcome of the polymerization is affected by the ratios of monomer, initiator, and catalyst used as well as the reaction concentration, solvent, and nature of the light source. Temporal control over the polymerization can be exercised by turning the visible light source off and on. Low dispersities of the resultant polymers as well as the ability to chain-extend to form block copolymers suggest control over the polymerization, while chain end-group analysis provides evidence supporting an atom-transfer radical polymerization mechanism.

A method for the atom transfer radical polymerization of functionalized vinyl monomers using perylene as a visible-light photocatalyst is described.

使用苝作为可见光光催化功能化的乙烯基单体原子转移自由基聚合

A standardized technique for atom transfer radical polymerization of vinyl monomers using perylene as a visible-light photocatalyst is presented. The ...

On-line Analysis of Nitrogen Containing Compounds in Complex Hydrocarbon Matrixes

The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The composition of heavy crude oils and shale oils varies substantially depending on the origin of the mixture. In particular they contain an increased amount of nitrogen containing compounds compared to the conventionally used sweet crude oils. As nitrogen compounds have an influence on the operation of thermal processes occurring in coker units and steam crackers, and as some species are considered as environmentally hazardous, a detailed analysis of the reactions involving nitrogen containing compounds under pyrolysis conditions provides valuable information. Therefore a novel method has been developed and validated with a feedstock containing a high nitrogen content, i.e., a shale oil. First, the feed was characterized offline by comprehensive two-dimensional gas chromatography (GC &#215; GC) coupled with a nitrogen chemiluminescence detector (NCD). In a second step the on-line analysis method was developed and tested on a steam cracking pilot plant by feeding pyridine dissolved in heptane. The former being a representative compound for one of the most abundant classes of compounds present in shale oil. The composition of the reactor effluent was determined via an in-house developed automated sampling system followed by immediate injection of the sample on a GC &#215; GC coupled with a time-of-flight mass spectrometer (TOF-MS), flame ionization detector (FID) and NCD. A novel method for quantitative analysis of nitrogen containing compounds using NCD and 2-chloropyridine as an internal standard has been developed and demonstrated.

A method combining comprehensive two-dimensional gas chromatography with nitrogen chemiluminescence detection has been developed and applied to on-line analysis of nitrogen containing compounds in a complex hydrocarbon matrix.

在线含硫化合物在复杂油气矩阵氮分析

The shift to heavy crude oils and the use of alternative fossil resources such as shale oil are a challenge for the petrochemical industry. The ...

Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by &#960;-&#960; Stacking Interactions

In this study, an amphiphilic copolymer that includes a core-forming block with phenyl groups was synthesized by living anionic polymerization of phenyl glycidyl ether (PheGE) on methoxy-polyethylene glycol (mPEG-b-PPheGE). Characterization of the copolymer revealed a narrow molecular distribution (PDI &#60; 1.03) and confirmed the degree of polymerization of mPEG122-b-(PheGE)15. The critical micelle concentration of the copolymer was evaluated using an established fluorescence method with the aggregation behavior evaluated by dynamic light scattering and transmission electronic microscopy. The potential of the copolymer for use in drug delivery applications was evaluated in a preliminary manner including in vitro biocompatibility, loading and release of the hydrophobic anti-cancer drug doxorubicin (DOX). A stable micelle formulation of DOX was prepared with drug loading levels up to 14% (wt%), drug loading efficiencies &#62; 60% (w/w) and sustained release of drug over 4 days under physiologically relevant conditions (acidic and neutral pH, presence of albumin). The high drug loading level and sustained release is attributed to stabilizing &#960;-&#960; interactions between DOX and the core-forming block of the micelles.

The key steps of living anionic polymerization of phenyl glycidyl ether (PheGE) on methoxy-polyethylene glycol (mPEG-b-PPheGE) are described. The resulting block copolymer micelles (BCMs) were loaded with doxorubicin 14% (wt%) and sustained release of drug over 4 days under physiologically relevant conditions was obtained.

一个两亲性共聚物的阴离子聚合通过π-π堆积作用稳定嵌段共聚物胶束的制备

In this study, an amphiphilic copolymer that includes a core-forming block with phenyl groups was synthesized by living anionic polymerization of phenyl ...

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes

Norbornene can be polymerized by a variety of mechanisms, including insertion polymerization whereby the double bond is polymerized and the bicyclic nature of the monomer is conserved. The resulting polymer, polynorbornene, has a very high glass transition temperature, Tg, and interesting optical and electrical properties. However, the polymerization of functional norbornenes by this mechanism is complicated by the fact that the endo substituted norbornene monomer has, in general, a very low reactivity. Furthermore, the separation of the endo substituted monomer from the exo monomer is a tedious task. Here, we present a simple protocol for the polymerization of substituted norbornenes (endo:exo ca. 80:20) bearing either a carboxylic acid or a pendant double bond. The process does not require that both isomers be separated, and proceeds with low catalyst loadings (0.01 to 0.02 mol%). The polymer bearing pendant double bonds can be further transformed in high yield, to afford a polymer bearing pendant epoxy groups. These simple procedures can be applied to prepare polynorbornenes with a variety of functional groups, such as esters, alcohols, imides, double bonds, carboxylic acids, bromo-alkyls, aldehydes and anhydrides.

We describe the catalytic insertion polymerization of 5-norbornene-2-carboxylic acid and 5-vinyl-2-norbornene to form functional polymers with a very high glass transition temperature.

功能性降冰片烯的催化聚合插入一种简单高效的协议

Norbornene can be polymerized by a variety of mechanisms, including insertion polymerization whereby the double bond is polymerized and the bicyclic ...

Determination of Carbonyl Functional Groups in Bio-oils by Potentiometric Titration: The Faix Method

Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. Specifically, carbonyls cause an increase in viscosity (often referred to as &#39;aging&#39;) during storage of bio-oils. As such, carbonyl content has previously been used as a method of tracking bio-oil aging and condensation reactions with less variability than viscosity measurements. Additionally, carbonyls are also responsible for coke formation in bio-oil upgrading processes. Given the importance of carbonyls in bio-oils, accurate analytical methods for their quantification are very important for the bio-oil community. Potentiometric titration methods based on carbonyl oximation have long been used for the determination of carbonyl content in pyrolysis bio-oils. Here, we present a modification of the traditional carbonyl oximation procedures that results in less reaction time, smaller sample size, higher precision, and more accurate carbonyl determinations. While traditional carbonyl oximation methods occur at room temperature, the Faix method presented here occurs at an elevated temperature of 80 &#176;C.

Here we present a potentiometric titration technique for accurately quantifying carbonyl compounds in pyrolysis bio-oils.

该Faix方法:生物油羰基官能团通过电位滴定法测定

Carbonyl compounds present in bio-oils are known to be responsible for bio-oil property changes upon storage and during upgrading. Specifically, carbonyls ...