Name: a simple and efficient protocol for the catalytic insertion polymerization of functional norbornenes
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The authors acknowledge funding from Fonds de Recherche du Qu&#233;bec - Nature et Technologies, from Conseil Recherches en Sciences Naturelles et G&#233;nie (program INNOV) and PrimaQu&#233;bec.

1. Preparation of Poly(5-norbornene-2-carboxylic acid), PNBE(CO2H)
<ol>
	<li>Preparation of the monomer NBE(CO2H)
	<ol>
		<li>Weigh out acrylic acid (AA) (327 g, 4.5 mol, 2 eq.) and hydroquinone (4.9 g, 4.5 x 10-2 mol, 0.02 eq.) and add them to a 2 L round-bottom flask equipped with a condenser and a magnetic stir bar. Heat the flask at 150 &#176;C using a silicone oil bath.</li>
		<li>Once reflux is settled, add DCPD (300 g, 2.3 mol, 1 eq.) in a single portion, and the...

<ol>
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E., Sen, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Addition+Polymerization+of+Functionalized+Norbornenes:+The+Effect+of+Size+Stereochemistry,+and+Coordinating+Ability+of+the+Substituent.">Addition Polymerization of Functionalized Norbornenes: The Effect of Size Stereochemistry, and Coordinating Ability of the Substituent.</a> Organometallics. 23 (8), 1680-1683 (2004).</li><li>Hennis, A. D., Polley, J. D., 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=Novel,+efficient,+palladium-based+system+for+the+polymerization+of+norbornene+derivatives:+Scope+and+mechanism.">Novel, efficient, palladium-based system for the polymerization of norbornene derivatives: Scope and mechanism.</a> Organometallics. 20 (13), 2802-2812 (2001).</li><li>Commarieu, B., Claverie, J. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bypassing+the+lack+of+reactivity+of+endo-substituted+norbornenes+with+the+catalytic+rectification-insertion+mechanism.">Bypassing the lack of reactivity of endo-substituted norbornenes with the catalytic rectification-insertion mechanism.</a> Chem. Sci. 6 (4), 2172-2182 (2015).</li><li>Commarieu, B., Potier, J., 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=Ultrahigh+Tg+epoxy+thermosets+based+on+insertion+polynorbornenes.">Ultrahigh Tg epoxy thermosets based on insertion polynorbornenes.</a> Macromoecules. 49 (3), 920-925 (2016).</li><li>Pirrung, M. 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Chem. 2 (1), 26-30 (2012).</li><li>Huertas, D., Florscher, M., Dragojlovic, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solvent-free+Diels-Alder+reactions+of+in+situ+generated+cyclopentadiene.">Solvent-free Diels-Alder reactions of in situ generated cyclopentadiene.</a> Green Chem. 11 (1), 91-95 (2009).</li><li>Pierre, F., Commarieu, B., Tavares, A. C., Claverie, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+Tg+sulfonated+insertion+polynorbornene+ionomers+prepared+by+catalytic+insertion+polymerization.">High Tg sulfonated insertion polynorbornene ionomers prepared by catalytic insertion polymerization.</a> Polymer. 86, 91-97 (2016).</li><li>Woo, H. G., Li, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Advanced functional materials, Chapter 1.6.8,30. 1, (2011).</li><li>Kim, D. -. G., Bell, A., Register, R. a. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Living+vinyl+addition+polymerization+of+substituted+norbornenes+by+a+t-Bu3P-Ligated+Methylpalladium+Complex.">Living vinyl addition polymerization of substituted norbornenes by a t-Bu3P-Ligated Methylpalladium Complex.</a> ACS Macro Letters. 4 (3), 327-330 (2015).</li><li>Seung, H., S, A., Baek, K., Sang, S., Intech, S. i. l. a. g. u. i. ,. M. .. 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The method proposed here is simple, and readily amenable to scale-up. All chemicals could be used as received without any purification. Note that performing the reaction at a lower scale (e.g. scales &#8804;1 g) usually yields lower yields due to an unavoidable loss of material during the handling and the collection.
The catalysts are formed in situ upon the reaction of commercial Pd compounds with cationizing agents. In our hands, the yield of the reaction as well as the cha...

Norbornene, NBE, the Diels-Alder adduct of ethylene and cyclopentadiene (obtained by &#34;cracking&#34; of dicyclopentadiene (DCPD)), is readily polymerized using either free-radical polymerization,1 cationic polymerization,2 ring-opening metathesis polymerization3 and catalytic insertion polymerization.4,5,6,7 Unlike the other mechanisms, the catalytic insertion polymerization leads to the formation of a very high glass-transition temperature (Tg) polymer whereby the bicyclic backbone of NBE is conserved. A variety of catalysts such as metallocene catalysts and late transition metal catalysts can be used to promote the polymerization of NBE.4,5,6,7 However, due to its low solubility and due to difficulties associated with the processing of a very high Tg polymer, the PNBE homopolymer has, to our knowledge, never found any use.
Functional polynorbornenes (PNBEs) have been the object of considerable scrutiny for the last 20 years, because they combine the high Tg imparted by the bicyclic rigid repeat unit as well as desirable properties endowed by their functionalities.8,9,10 NBE monomers are obtained from rather simple and inexpensive feedstocks, using a one-step Diels-Alder reaction between cyclopentadiene and a functionalized dienophile. However, the Diels-Alder reaction leads to two stereoisomers, endo and exo, which have very different reactivities.11,12 In fact, the endo stereoisomer is less reactive than exo form and deactivates the catalyst.11,12 Thus, in the past, the preparation of functional polynorbornenes usually required the separation of the endo and exo stereoisomers, and only the exo stereoisomer was used. Such a separation procedure was time-consuming, and led to the accumulation of unreacted endo stereoisomers as undesirable waste.
Recently we have shown that the polymerization of functionalized NBEs containing both stereoisomers is in fact feasible.13 We have thus been able to prepare a variety of substituted PNBEs, containing functional groups such as esters, anhydrides, aldehydes, imides, alcohols and double bonds. Due to their high Tg and functionality, these polymers show desirable properties. We describe here two methods to prepare functional polymers. The first one leads to the synthesis of the water soluble polymer poly(5-norbornene-2-carboxylic acid), PNBE(CO2H), using a cationic Pd catalyst (Figure 1).13,14 The same polymerization method can be used to prepare functional PNBEs with various pendant functionalities, such as esters, alcohols, imides, bromo-alkyls, aldehydes and anhydrides. In our hands, this cationic Pd catalyst cannot be used for NBEs containing pendant double bonds such as 5-vinyl-2-norbornene. In this case, a partial insertion of the pendant double bond during the polymerization leads to the formation of a cross-linked material. Therefore, we present here a second method dedicated to the formation of poly(5-vinyl-2-norbornene), PNBE(vinyl), using Pd2(dba)3:AgSbF6:PPh3 as an in situ catalyst.14 The pendant vinyl groups of the polymer are then further epoxidized, to lead to the formation of PNBE(epoxy) (Figure 1). Both PNBE(CO2H) and PNBE(epoxy) have been found to lead to the formation of thermoset resins with a Tg as high as 350 &#176;C.14 Thus, the simple method described here allows one to efficiently prepare polymers with a very high Tg and having a variety of functional groups, which can be used for numerous applications.
<img alt="Figure 1" src="/files/ftp_upload/54552/54552fig1.jpg" /> 
Figure 1: Functional PNBEs prepared by Pd catalyzed polymerization. (A) preparation of PNBE(CO2H), (B) preparation of PNBE(vinyl) and PNBE(epoxy). The dashed bond indicates a mixture of endo and exo isomers. <a href="http://cloudflare.jove.com/files/ftp_upload/54552/54552fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

<table border="0" cellpadding="0" cellspacing="0" width="945">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">acrylic acid</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">147230</td>
			<td style="width:299px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">hydroquinone</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td>H9003</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">dicyclopendadiene</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td align="left">454338</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">palladium allyl dichloride dimer</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td>222380</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">silver hexfluoro antimonate</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">227730</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">liquid nitrogen</td>
			<td style="width:241px;">Local Facility</td>
			<td style="width:135px;">NA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">ethyl acetate</td>
			<td style="width:241px;">Fischer Scientific</td>
			<td>E14520</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">5-vinyl-2-norbornene</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">148679</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">toluene</td>
			<td style="width:241px;">Fischer Scientific</td>
			<td>T290-4</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">palladium dba</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">227994</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">triphenyl phosphine</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">93090</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">silica gel 40-63 microns</td>
			<td style="width:241px;">Silicycle</td>
			<td style="width:135px;">Siliaflash</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">methanol</td>
			<td style="width:241px;">Fischer Scientific</td>
			<td>BPA412-20</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">dichloromethane</td>
			<td style="width:241px;">EMD Millipore</td>
			<td>DX08311</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">formic acid</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">F0507</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">acetic acid</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td>320099</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:271px;">hydrogen peroxide solution</td>
			<td style="width:241px;">Sigma-Aldrich</td>
			<td style="width:135px;">216763</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:271px;">acetone</td>
			<td style="width:241px;">Fischer Scientific</td>
			<td>A18-200</td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

The NBE monomers are prepared by simple Diels-Alder reaction of DCPD and a suitable dienophile, for example acrylic acid (AA). Normally, DCPD is cracked to yield cyclopentadiene (CPD) before reaction.17 Freshly cracked CPD is then engaged in the Diels-Alder reaction. However, in this protocol, both cracking and Diels-Alder steps are performed concomitantly, in a one-pot reaction. Thus, as soon as CPD is formed, it reacts with AA to yield 5-norbornene-2-carboxylic a...

Watch this Scientific Journal Video about A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes at JoVE.com

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

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.

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

The overall goal of this synthetic procedure is to prepare functional insertion polynorbornenes, which are highly functional polymers with a very high glass transition temperature. The main advantage of this technique is that it's possible to access high performance polymers bearing highly reactive functional groups such as epoxy groups or acid groups via a simple experimental protocol. Generally, researchers that are new to catalytic polymer synthesis will struggle because the synthesis must be performed using very high standards of purity, but here, in the process we're going to describe, the synthesis can be performed easily with no special purification step.Demonstrating part of the procedure will be Moubarak Compaore, a graduate student in the Claverie laboratory. To begin this procedure, set up a one liter round bottom flask with a condenser and stir bar. Add 327 grams of acrylic acid and 4.9 grams of hydroquinone to the flask.Then use a heating block to heat the mixture to 150 degrees Celsius. Once the refluxing has settled, add 300 grams of DCPD. Then increase the temperature to 170 degrees Celsius for 16 hours.The solution color will change from clear to yellow-brown. Using a Pasteur pipette, extract a sample. Analyze by proton NMR, using deuterated chloroform as the solvent.Next, remove the condenser from the round bottom flask. Replace it with a simple distillation setup connected to a condenser circulating cold water. Place the reaction setup under vacuum and set the pressure to one millimeter mercury.Then heat to 100 degrees Celsius for approximately one hour. Collect and discard the clear liquid that boils off. Replace the collection flask with a 250 milliliter round bottom flask.Heat to 155 degrees Celsius for seven hours to distill the NBE carboxylic acid. Analyze the distilled liquid by proton NMR to determine the purity and endo to exo proportions. Then add 300 grams of NBE carboxylic acid to a 500 milliliter round bottom flask equipped with a magnetic stir bar.Degas the NBE carboxylic acid by bubbling nitrogen for 40 minutes using a slow stirring rate for the stir bar. Add 76 milligrams of allylpalladium(II)chloride dimer. Then add 180 milligrams of silver antimonate.Increase the stirring rate and heat the solution to 70 degrees Celsius under a slight nitrogen flux for 36 hours. Next, cool the flask with liquid nitrogen. Using a spatula, break the polymer into small pieces.Add 750 milliliters of ethyl acetate to a two liter beaker equipped with a magnetic stir bar. Then add the polymer chunks under vigorous stirring. Allow the solution to continue stirring for two hours.After stirring is complete, filter the solution using a Buchner funnel equipped with filter paper. Wash the polymer with 500 milliliters of ethyl acetate three times, then dry the polymer in a vacuum oven at 50 degrees Celsius for 12 hours. Separately degas 100 grams of toluene and 100 grams of NBE(vinyl)by bubbling with nitrogen gas for 30 minutes.After that, place both in the glove box. In the glove box, add the toluene into a 250 milliliter round bottom flask. Next, successively add 76 milligrams of PD2(DBA)3, 68 milligrams of silver antimonite and 43 milligrams of triphenylphosphine to the toluene solution.Then add the degassed NBE(vinyl)and stir at 70 degrees Celsius for 72 hours. Once stirring is complete, remove the solution from the glove box and transfer it into a one liter glass bottle equipped with a magnetic stir bar. Add 200 milliliters of fresh toluene and stir.Then add 10 grams of silica powder and continue stirring at room temperature for 16 hours. After stirring is complete, let the solution settle for two hours to allow the silica particles to sedimentate. Filter the settled solution through a Buchner funnel equipped with filter paper.Rinse the silica particles with fresh toluene and filter it through the Buchner funnel. Next, add 1.2 liters of methanol to a fresh four liter beaker equipped with a magnetic stir bar. Gradually add this solution of toluene and polymer to the beaker under vigorous stirring.Continue stirring for 30 minutes. After stirring is complete, filter the polymer using a Buchner funnel and filter paper. Wash the polymer with 400 milliliters of methanol three times.Analyze the polymer purity by proton NMR to determine if the residual monomer is present. If so, perform one additional wash with methanol. After washing is complete, dry the PNBE(vinyl)under vacuum at room temperature overnight.Add 150 grams of dichloromethane to a 500 milliliter round bottom flask equipped with a magnetic stir bar and a condenser. Then add 15 grams of PNBE(vinyl)with stirring. Once the polymer has completely dissolved, place the flask in an ice bath to cool for 15 minutes.In a fresh beaker, mix 30 grams of formic acid and five grams of acetic acid. Add this acid solution to the flask and let it cool for 15 minutes. Next, add 75 grams of a 30%aqueous solution of hydrogen peroxide and stir the solution for 18 hours.After this, remove a small sample. Precipitate the polymer with acetone and analyze with proton NMR as outlined in the text protocol. If the signal for the double bond has not decreased sufficiently, continue stirring the reaction, analyzing by proton NMR hourly.Once the signal for the double bond has decreased sufficiently, add 750 milliliters of acetone to a fresh four liter beaker equipped with a magnetic stir bar. Gradually add the polymer solution under vigorous stirring. Let the solution continue to stir for 15 minutes.After that, filter the polymer using a Buchner funnel and filter paper. Wash the polymer with 200 milliliters of acetone four times. Finally, dry the polymer under vacuum at room temperature overnight.In this procedure, polymers are obtained by catalyzed polymerization and collected in the form of dry powders. Representative results for the proton NMR analysis of the polymers can be seen here. This analysis confirms the epoxidation of PNBE(vinyl)The decreasing ratio between the integrals of the vinyl group and the other protons in the PNBE(epoxy)spectrum proves the efficacy of this epoxidation procedure, with 97%of PNBE(vinyl)being converted to PNBE(epoxy)FTIR spectroscopy is also used to confirm the outcome of the epoxidation reaction.This is seen by the apparition of a characteristic peak at 875 inverse centimeters and the disappearance of the 904 inverse centimeter and 992 inverse centimeter peaks, which are observed in the PNBE(vinyl)polymer. So once mastered, an ordinary scale of either polymer, be it polynorbornene epoxy or polynorbornene acid, can be prepared in less than a week with minimal manipulation time.

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A Simple and Rapid Protocol for Measuring Neutral Lipids in Algal Cells Using Fluorescence

Algae are considered excellent candidates for renewable fuel sources due to their natural lipid storage capabilities. Robust monitoring of algal fermentation processes and screening for new oil-rich strains requires a fast and reliable protocol for determination of intracellular lipid content. Current practices rely largely on gravimetric methods to determine oil content, techniques developed decades ago that are time consuming and require large sample volumes. In this paper, Nile Red, a fluorescent dye that has been used to identify the presence of lipid bodies in numerous types of organisms, is incorporated into a simple, fast, and reliable protocol for measuring the neutral lipid content of Auxenochlorella protothecoides, a green alga. The method uses ethanol, a relatively mild solvent, to permeabilize the cell membrane before staining and a 96 well micro-plate to increase sample capacity during fluorescence intensity measurements. It has been designed with the specific application of monitoring bioprocess performance. Previously dried samples or live samples from a growing culture can be used in the assay.

A simple protocol to determine the neutral lipid content of algal cells using a Nile Red staining procedure is described. This time-saving technique offers an alternative to traditional gravimetric-based lipid quantification protocols. It has been designed for the specific application of monitoring bioprocess performance.

Algae are considered excellent candidates for renewable fuel sources due to their natural lipid storage capabilities. Robust monitoring of algal ...

Synthesis and Catalytic Performance of Gold Intercalated in the Walls of Mesoporous Silica

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties of the materials were investigated. We used a one pot sol-gel approach to intercalate gold nano particles in the walls of mesoporous silica. To start with the synthesis, P123 was used as template to form micelles. Then TESPTS was used as a surface modification agent to intercalate gold nano particles. Following this process, TEOS was added in as a silica source which underwent a polymerization process in acid environment. After hydrothermal processing and calcination, the final product was acquired. Several techniques were utilized to characterize the porosity, morphology and structure of the gold intercalated mesoporous silica. The results showed a stable structure of mesoporous silica after gold intercalation. Through the oxidation of benzyl alcohol as a benchmark reaction, the GMS materials showed high selectivity and recyclability.

Here, we present a protocol with a sol-gel process to synthesize gold intercalated in the walls of mesoporous materials (GMS), which is confirmed to possess a mesoporous matrix with gold intercalated in the walls imparting great stability and recyclability.

As a promising catalytically active nano reactor, gold nanoparticles intercalated in mesoporous silica (GMS) were successfully synthesized and properties ...

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.

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

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel &#945;-diimine ethylene polymerization catalyst. Initial polymerizations with the catalyst lead to optimized reaction conditions, including catalyst concentration, ethylene pressure and reaction time. Using gas-uptake data for these reactions, a procedure to calculate the initial rate of propagation (kp) is presented. Using the optimized conditions, the ability of the nickel &#945;-diimine polymerization catalyst to undergo chain transfer with diethylzinc (ZnEt2) during ethylene polymerization was investigated. A procedure to assess the ability of the catalyst to undergo chain transfer (from molecular weight and 13C NMR data), calculate the degree of chain transfer, and calculate chain transfer rates (ke) is presented.

A protocol for the high-throughput analysis of polymerization catalyst, chain transfer polymerizations, polyethylene characterization, and reaction kinetic analysis is presented.

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel ...

A Protocol for the Production of Gliadin-cyanoacrylate Nanoparticles for Hydrophilic Coating

This article presents a protocol for the production of protein-based nanoparticles that changes the hydrophobic surface to hydrophilic by a simple spray coating. These nanoparticles are produced by the polymerization reaction of alkyl cyanoacrylate on the surface of cereal protein (gliadin) molecules. Alkyl cyanoacrylate is a monomer that instantly polymerizes at RT when it is applied to the surface of materials. Its polymerization reaction is initiated by the trace amounts of weakly basic or nucleophilic species on the surface, including moisture. Once polymerized, the polymerized alkyl cyanoacrylates show a strong affinity with the object materials because nitrile groups are in the backbone of poly (alkyl cyanoacrylate). Proteins also work as initiator for this polymerization because they contain amine groups that can initiate the polymerization of cyanoacrylate. If aggregated protein is used as an initiator, protein aggregate is surrounded by the hydrophobic poly(alkyl cyanoacrylate) chains after the polymerization reaction of alkyl cyanoacrylate. By controlling the experimental condition, particles in the nanometer range are produced. The produced nanoparticles readily adsorb to the surface of most materials including glass, metals, plastics, wood, leather, and fabrics. When the surface of a material is sprayed with the produced nanoparticle suspension and rinsed with water, the micellar structure of nanoparticle changes its conformation, and the hydrophilic proteins are exposed to the air. As a result, the nanoparticle-coated surface changes to hydrophilic.

This article presents a protocol for the production of protein-based nanoparticles that changes the hydrophobic surface to hydrophilic. The produced nanoparticle is an assembly of gliadin-cyanoacrylate diblock copolymers. Spray coating with the produced nanoparticle changes the surface of target material to a hydrophilic surface.

This article presents a protocol for the production of protein-based nanoparticles that changes the hydrophobic surface to hydrophilic by a simple spray ...

Facile Synthesis of Worm-like Micelles by Visible Light Mediated Dispersion Polymerization Using Photoredox Catalyst

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins with the synthesis of a hydrophilic poly(oligo(ethylene glycol) methyl ether methacrylate) (POEGMA) homopolymer using reversible addition-fragmentation chain-transfer (RAFT) polymerization. Under mild visible light irradiation (&#955; = 460 nm, 0.7 mW/cm2), this macro-chain transfer agent (macro-CTA) in the presence of a ruthenium based photoredox catalyst, Ru(bpy)3Cl2 can be chain extended with a second monomer to form a well-defined block copolymer in a process known as Photoinduced Electron Transfer RAFT (PET-RAFT). When PET-RAFT is used to chain extend POEGMA with benzyl methacrylate (BzMA) in ethanol (EtOH), polymeric nanoparticles with different morphologies are formed in situ according to a polymerization-induced self-assembly (PISA) mechanism. Self-assembly into nanoparticles presenting POEGMA chains at the corona and poly(benzyl methacrylate) (PBzMA) chains in the core occurs in situ due to the growing insolubility of the PBzMA block in ethanol. Interestingly, the formation of highly pure worm-like micelles can be readily monitored by observing the onset of a highly viscous gel in situ due to nanoparticle entanglements occurring during the polymerization. This process thereby allows for a more reproducible synthesis of worm-like micelles simply by monitoring the solution viscosity during the course of the polymerization. In addition, the light stimulus can be intermittently applied in an ON/OFF manner demonstrating temporal control over the nanoparticle morphology.

This article describes a process for producing polymeric self-assembled nanoparticles using visible light mediated dispersion polymerization. Using low energy visible light to control the polymerization allows for the reproducible formation of self-assembled worm-like micelles at high solids content.

Presented herein is a protocol for the facile synthesis of worm-like micelles by visible light mediated dispersion polymerization. This approach begins ...

Laboratory Production of Biofuels and Biochemicals from a Rapeseed Oil through Catalytic Cracking Conversion

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil (HGO) for production of transportation fuels through a fluid catalytic cracking (FCC) route. Cracking experiments are performed with a fully automated reaction unit at a fixed weight hourly space velocity (WHSV) of 8 hr-1, 490-530 &#176;C, and catalyst/oil ratios of 4-12 g/g. When a feed is in contact with catalyst in the fluid-bed reactor, cracking takes place generating gaseous, liquid, and solid products. The vapor produced is condensed and collected in a liquid receiver at -15 &#176;C. The non-condensable effluent is first directed to a vessel and is sent, after homogenization, to an on-line gas chromatograph (GC) for refinery gas analysis. The coke deposited on the catalyst is determined in situ by burning the spent catalyst in air at high temperatures. Levels of CO2 are measured quantitatively via an infrared (IR) cell, and are converted to coke yield. Liquid samples in the receivers are analyzed by GC for simulated distillation to determine the amounts in different boiling ranges, i.e., IBP-221 &#176;C (gasoline), 221-343 &#176;C (light cycle oil), and 343 &#176;C+ (heavy cycle oil). Cracking of a feed containing canola oil generates water, which appears at the bottom of a liquid receiver and on its inner wall. Recovery of water on the wall is achieved through washing with methanol followed by Karl Fischer titration for water content. Basic results reported include conversion (the portion of the feed converted to gas and liquid product with a boiling point below 221 &#176;C, coke, and water, if present) and yields of dry gas (H2-C2's, CO, and CO2), liquefied petroleum gas (C3-C4), gasoline, light cycle oil, heavy cycle oil, coke, and water, if present.

This paper presents an experimental method to produce biofuels and biochemicals from canola oil mixed with a fossil-based feed in the presence of a catalyst at mild temperatures. Gaseous, liquid, and solid products from a reaction unit are quantified and characterized. Conversion and individual product yields are calculated and reported.

The work is based on a reported study which investigates the processability of canola oil (bio-feed) in the presence of bitumen-derived heavy gas oil ...

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient radiolabeling of DBCO-group-functionalized gold nanoparticles using a copper-free click reaction. Radioiodination of the stannylated precursor (2) was carried out by using [125I]NaI and chloramine T as an oxidant at room temperature for 15 min. After HPLC purification of the crude product, the purified 125I-labeled azide (1) was obtained with high radiochemical yield (75 &plusmn; 10%, n = 8) and excellent radiochemical purity (&gt;99%). For the synthesis of radiolabeled 13-nm-sized gold nanoparticles, the DBCO-functionalized gold nanoparticles (3) were prepared by using a thiolated polyethylene glycol polymer. A copper-free click reaction between 1 and 3 gave the 125I-labeled gold nanoparticles (4) with more than 95% of radiochemical yield as determined by radio-thin-layer chromatography (radio-TLC). These results clearly indicate that the present radiolabeling method using a strain-promoted copper-free click reaction will be useful for the efficient and convenient radiolabeling of DBCO-group-containing nanomaterials.

An Optimized Protocol for the Efficient Radiolabeling of Gold Nanoparticles by Using a 125I-labeled Azide Prosthetic Group

A detailed procedure for the synthesis of a 125I-labeled azide and the radiolabeling of dibenzocyclooctyne (DBCO)-group-conjugated, 13-nm-sized gold nanoparticles using a copper-free click reaction is described.

Here, we demonstrate a detailed protocol for the radiosynthesis of a 125I-labeled azide prosthetic group and its application to the efficient ...

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of NixNb1-xO nanoparticles with different atomic compositions (x = 0.03, 0.08, 0.15, and 0.20) have been prepared by chemical precipitation. These NixNb1-xO catalysts are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The study revealed the sponge-like and fold-like appearance of Ni0.97Nb0.03O and Ni0.92Nb0.08O on the NiO surface, and the larger surface area of these NixNb1-xO catalysts, compared with the bulk NiO. Maximum surface area of 173 m2/g can be obtained for Ni0.92Nb0.08O catalysts. In addition, the catalytic hydroconversion of lignin-derived compounds using the synthesized Ni0.92Nb0.08O catalysts have been investigated.

Chemical Precipitation Method for the Synthesis of Nb2O5 Modified Bulk Nickel Catalysts with High Specific Surface Area

A protocol for the synthesis of sponge-like and fold-like Ni1-xNbxO nanoparticles by chemical precipitation is presented.

We demonstrate a method for the synthesis of NixNb1-xO catalysts with sponge-like and fold-like nanostructures. By varying the Nb:Ni ratio, a series of ...

Fabrication and Testing of Catalytic Aerogels Prepared Via Rapid Supercritical Extraction

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three preparation methods are described: (a) the incorporation of metal salts into silica or alumina wet gels using an impregnation method; (b) the incorporation of metal salts into alumina wet gels using a co-precursor method; and (c) the addition of metal nanoparticles directly into a silica aerogel precursor mixture. The methods utilize a hydraulic hot press, which allows for rapid (&#60;6 h) supercritical extraction and results in aerogels of low density (0.10 g/mL) and high surface area (200-800 m2/g). While the work presented here focuses on the use of copper salts and copper nanoparticles, the approach can be implemented using other metal salts and nanoparticles. A protocol for testing the three-way catalytic ability of these aerogels for automotive pollution mitigation is also presented. This technique uses custom-built equipment, the Union Catalytic Testbed (UCAT), in which a simulated exhaust mixture is passed over an aerogel sample at a controlled temperature and flow rate. The system is capable of measuring the ability of the catalytic aerogels, under both oxidizing and reducing conditions, to convert CO, NO and unburned hydrocarbons (HCs) to less harmful species (CO2, H2O and N2). Example catalytic results are presented for the aerogels described.

Here we present protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms. Methods for preparing materials using copper salts and copper-containing nanoparticles are featured. Catalytic testing protocols demonstrate the effectiveness of these aerogels for three-way catalysis applications.

Protocols for preparing and testing catalytic aerogels by incorporating metal species into silica and alumina aerogel platforms are presented. Three ...