Name: atom transfer radical polymerization of functionalized vinyl monomers using perylene as a visible light photocatalyst
Uploaded: 2016-04-22T13:00:00
Description: Watch this Scientific Journal Video about Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst at JoVE.com

The authors would like to acknowledge the University of Colorado Boulder for its support of this work.

CAUTION: Many of the chemicals used in this protocol are hazardous substances. Consult Material Safety Data Sheets (MSDS) and use appropriate personal protective equipment (PPE) when working with these substances.
1. Purification, Preparation, and Storage of Reagents
<ol>
	<li>Purify all solvents to be used using a solvent purification system according to manufacturer&#39;s protocol. If a solvent purification system is not available, use drying agents (e.g., molecular sieves, CaH<su...

<ol>
	<li>Bates, F. S., Hillmyer, M. A., Lodge, T. P., Bates, C. M., Delaney, K. T., Fredrickson, G. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiblock+Polymers:+Panacea+or+Pandora's+Box.">Multiblock Polymers: Panacea or Pandora's Box.</a> Science. 336 (6080), 434-440 (2012).</li><li>Hawker, C. J., Wooley, K. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Convergence+of+Synthetic+Organic+and+Polymer+Chemistries.">The Convergence of Synthetic Organic and Polymer Chemistries.</a> Science. 309 (5738), 1200-1205 (2005).</li><li>di Lena, F., Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transition+Metal+Catalysts+for+Controlled+Radical+Polymerization.">Transition Metal Catalysts for Controlled Radical Polymerization.</a> Prog. Polym. Sci. 35 (8), 959-1021 (2010).</li><li>Rosen, B. M., Percec, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Single-Electron+Transfer+and+Single-Electron+Transfer+Degenerative+Chain+Transfer+Living+Radical+Polymerization.">Single-Electron Transfer and Single-Electron Transfer Degenerative Chain Transfer Living Radical Polymerization.</a> Chem. Rev. 109 (11), 5069-5119 (2009).</li><li>Moad, G., Rizzardo, E., Thang, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Toward+Living+Radical+Polymerization.">Toward Living Radical Polymerization.</a> Acc. Chem. Res. 41 (9), 1133-1142 (2008).</li><li>Braunecker, W. A., Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Controlled/living+Radical+Polymerization:+Features,+Developments,+and+Perspectives.">Controlled/living Radical Polymerization: Features, Developments, and Perspectives.</a> Prog. Polym. Sci. 32 (1), 93-146 (2007).</li><li>Kamigaito, M., Ando, T., Sawamoto, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metal-Catalyzed+Living+Radical+Polymerization.">Metal-Catalyzed Living Radical Polymerization.</a> Chem. Rev. 101 (12), 3689-3746 (2001).</li><li>Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+and+Classifications+of+Controlled/Living+Radical+Polymerizations.">Comparison and Classifications of Controlled/Living Radical Polymerizations.</a> ACS Symp. Ser. 768 (1), 2-26 (2000).</li><li>Matyjaszewski, K., Tsarevsky, N. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macromolecular+Engineering+by+Atom+Transfer+Radical+Polymerization.">Macromolecular Engineering by Atom Transfer Radical Polymerization.</a> J. Am. Chem. Soc. 136 (18), 6513-6533 (2013).</li><li>Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atom+Transfer+Radical+Polymerization+(ATRP):+Current+Status+and+Future+Perspectives.">Atom Transfer Radical Polymerization (ATRP): Current Status and Future Perspectives.</a> Macromolecules. 45 (10), 4015-4039 (2012).</li><li>Ouchi, M., Terashima, T., Sawamoto, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transition+Metal-Catalyzed+Living+Radical+Polymerization:+Toward+Perfection+in+Catalysis+and+Precision+Polymer+Synthesis.">Transition Metal-Catalyzed Living Radical Polymerization: Toward Perfection in Catalysis and Precision Polymer Synthesis.</a> Chem. Rev. 109 (11), 4963-5050 (2009).</li><li>Matyjaszewski, K., Tsarevsky, N. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanostructured+Functional+Materials+Prepared+by+Atom+Transfer+Radical+Polymerization.">Nanostructured Functional Materials Prepared by Atom Transfer Radical Polymerization.</a> Nat. Chem. 1 (4), 276-288 (2009).</li><li>Ouchi, M., Terashima, T., Sawamoto, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+Control+of+Radical+Polymerization+via+Transition+Metal+Catalysis:+From+Dormant+Species+to+Designed+Catalysts+for+Precision+Functional+Polymers.">Precision Control of Radical Polymerization via Transition Metal Catalysis: From Dormant Species to Designed Catalysts for Precision Functional Polymers.</a> Acc. Chem. Res. 41 (9), 1120-1132 (2008).</li><li>Matyjaszewski, K., Xia, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Atom+Transfer+Radical+Polymerization.">Atom Transfer Radical Polymerization.</a> Chem. Rev. 101 (9), 2921-2990 (2001).</li><li>Magenau, A. J. D., Strandwitz, N. C., Gennaro, A., Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrochemically+Mediated+Atom+Transfer+Radical+Polymerization.">Electrochemically Mediated Atom Transfer Radical Polymerization.</a> Science. 332 (6025), 81-84 (2011).</li><li>Matyjaszewski, K., 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=Diminishing+Catalyst+Concentration+in+Atom+Transfer+Radical+Polymerization+with+Reducing+Agents.">Diminishing Catalyst Concentration in Atom Transfer Radical Polymerization with Reducing Agents.</a> Proc. Natl. Acad. Sci. U.S.A. 103 (42), 15309-15314 (2006).</li><li>Moad, G., Rizzardo, E., Thang, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Living+Radical+Polymerization+by+the+RAFT+Process-+A+Second+Update.">Living Radical Polymerization by the RAFT Process- A Second Update.</a> Aust. J. Chem. 62 (11), 1402-1472 (2009).</li><li>Moad, G., Rizzardo, E., Thang, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Radical+Addition-Fragmentation+Chemistry+in+Polymer+Synthesis.">Radical Addition-Fragmentation Chemistry in Polymer Synthesis.</a> Polymer. 49 (5), 1079-1131 (2008).</li><li>Nicolas, 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=Nitroxide-Mediated+Polymerization.">Nitroxide-Mediated Polymerization.</a> Prog. Polym. Sci. 38 (1), 63-235 (2013).</li><li>Hawker, C. J., Bosman, A. W., Harth, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=New+Polymer+Synthesis+by+Nitroxide+Mediated+Living+Radical+Polymerizations.">New Polymer Synthesis by Nitroxide Mediated Living Radical Polymerizations.</a> Chem. Rev. 101 (12), 3661-3688 (2001).</li><li>Goto, A., Wakada, T., Fukuda, T., Tsujii, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+Systematic+Kinetic+Study+in+Reversible+Chain+Transfer+Catalyzed+Polymerizations+(RTCPs)+with+Germanium,+Tin,+Phosphorus,+and+Nitrogen+Catalysts.">A Systematic Kinetic Study in Reversible Chain Transfer Catalyzed Polymerizations (RTCPs) with Germanium, Tin, Phosphorus, and Nitrogen Catalysts.</a> Macromol. Chem. Phys. 211 (5), 594-600 (2010).</li><li>Goto, A., Ohtsuki, A., Ohfuji, H., Tanishima, M., Kaji, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reversible+Generation+of+a+Carbon-Centered+Radical+from+Alkyl+Iodide+Using+Organic+Salts+and+Their+Application+as+Organic+Catalysts+in+Living+Radical+Polymerization.">Reversible Generation of a Carbon-Centered Radical from Alkyl Iodide Using Organic Salts and Their Application as Organic Catalysts in Living Radical Polymerization.</a> J. Am. Chem. Soc. 135 (30), 11131-11139 (2013).</li><li>Goto, A., 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=Reversible+Complexation+Mediated+Living+Radical+Polymerization+(RCMP)+Using+Organic+Catalysts.">Reversible Complexation Mediated Living Radical Polymerization (RCMP) Using Organic Catalysts.</a> Macromolecules. 44 (22), 8709-8715 (2011).</li><li>Miyake, G. M., Theriot, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Perylene+as+an+Organic+Photocatalyst+for+the+Radical+Polymerization+of+Functionalized+Vinyl+Monomers+Through+Oxidative+Quenching+With+Alkyl+Bromides+and+Visible+Light.">Perylene as an Organic Photocatalyst for the Radical Polymerization of Functionalized Vinyl Monomers Through Oxidative Quenching With Alkyl Bromides and Visible Light.</a> Macromolecules. 47 (23), 8255-8261 (2014).</li><li>Miyake, G. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Organocatalyzed+Photoredox+Mediated+Polymerization+Using+Visible+Light.">Organocatalyzed Photoredox Mediated Polymerization Using Visible Light.</a> US Patent Application. 14, (2013).</li><li>Treat, N. 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=Metal-Free+Atom+Transfer+Radical+Polymerization.">Metal-Free Atom Transfer Radical Polymerization.</a> J. Am. Chem. Soc. 136 (45), 16096-16101 (2014).</li><li>Pan, X., Lamson, M., Yan, J., Matyjaszewski, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Photoinduced+Metal-Free+Atom+Transfer+Radical+Polymerization+of+Acrylonitrile.">Photoinduced Metal-Free Atom Transfer Radical Polymerization of Acrylonitrile.</a> ACS Macro Lett. 4 (2), 192-196 (2015).</li></ol>

Although the protocol demonstrates a specific example of this polymerization technique, the options available to the researcher performing this reaction are quite broad. Modifications can be made at a number of points throughout the protocol to allow for the optimization of whatever particular photoredox ATRP is being performed. As new monomers, initiators, and catalysts for this reaction come under investigation, the stoichiometry and solvent used to perform the reaction can and should be modified as part of optimizatio...

The synthesis of technologically advanced polymers requires precise control over polymer molecular weight, dispersity (&#208;), composition, and architecture.1,2 Controlled radical polymerizations (CRPs)3-8 have revolutionized the synthesis of well-defined polymers, with atom transfer radical polymerization (ATRP) being the most used CRP, largely due to operational simplicity and synthetic versatility.9-14 The crux of ATRP is the ability to reversibly deactivate the polymerization, controlling the equilibrium between a propagating radical and a dormant species. Enforcing a low concentration of active radicals greatly minimizes bimolecular termination pathways and allows for the synthesis of well-defined polymers. 
Traditional ATRP relies on a transition metal catalyst to mediate this equilibrium.3 These metal catalysts contaminate the polymer product and impede implementation in biomedical or electronic applications while also raising environmental concerns. Although significant strides have been made to reduce the catalyst concentration to ppm levels, these methodologies require more demanding experimental conditions and metal contamination is still not entirely eliminated.15,16
Reversible addition-fragmentation transfer17,18 and nitroxide-mediated polymerizations19,20 are CRPs that do not require metal catalysts, although they have been used less often than ATRP.3 Recently, reversible chain-transfer21 and reversible complexation22,23 variants of ATRP that can use organic catalysts were reported. However, these methodologies require the use of alkyl iodide initiators and are not effective with the alkyl bromides commonly employed in ATRP. A highly desirable CRP would match the performance, feasibility, and robustness of traditional ATRP while being catalyzed by an organic catalyst under mild conditions.
Here, we describe a methodology for the radical polymerization of functionalized vinyl monomers using perylene as a visible-light photocatalyst. Through optimization of parameters such as stoichiometry, concentration, time, and light flux, the molecular weight of the polymers can be controlled.24, 25 Similar methodologies have been recently introduced using phenothiazine derivatives as photocatalysts for metal-free ATRP.26, 27 Because researchers in the field of polymerization catalysis are constantly developing new catalytic systems, the ability to compare catalyst performance across a number of metrics is vital. This ability to make comparisons relies heavily upon procedural consistency and clarity on the part of the researchers performing the experiments. As such, it is our goal that this video will be used to help precisely communicate the methods by which these polymers are synthesized and characterized.

<table border="0" cellpadding="0" cellspacing="0" width="572">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">perylene, min 98.0%</td>
			<td style="width:92px;">TCI America</td>
			<td style="width:128px;">TCP0078-025G</td>
			<td style="width:147px;">purify by sublimation</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">N,N-dimethylformamide</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">EM-DX1726-1</td>
			<td style="width:147px;">Omnisolv</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:205px;">methyl methacrylate, 99%</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">200000-678</td>
			<td style="width:147px;">distilled prior to use, stored in refrigerator</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">ethyl &#945;-bromophenyl acetate&#160;</td>
			<td style="width:92px;">Aldrich</td>
			<td style="width:128px;">554065</td>
			<td style="width:147px;">distilled prior to use stored in refrigerator</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">butylated hydroxytoluene&#160;</td>
			<td style="width:92px;">Aldrich</td>
			<td style="width:128px;">W218405</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;">Chloroform-D</td>
			<td style="width:92px;">Cambridge Isotope Labs</td>
			<td style="width:128px;">DLM-7-100</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">tetrahydrofuran</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">EM-TX0279-1</td>
			<td style="width:147px;">Omnisolv</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">methanol</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">BDH1135</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">dichloromethane</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">EM-DX0831-1</td>
			<td style="width:147px;">Omnisolv</td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:205px;">styrene, 99%</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">AAAA18481-0F</td>
			<td style="width:147px;">distilled prior to use, stored in refrigerator</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">glass scintillation vial, 20 mL</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">66022-065</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">screw top vial, 2 mL</td>
			<td style="width:92px;">Agilent</td>
			<td style="width:128px;">5182-0715</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">septum cap for screw top vial</td>
			<td style="width:92px;">Agilent</td>
			<td style="width:128px;">5182-0717</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:205px;">heavy wall pressure vessel, 100 mL</td>
			<td style="width:92px;">Synthware</td>
			<td style="width:128px;">P160005&#160;</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">syringe, 1 mL norm-ject</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">89174-491</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">NMR tube</td>
			<td style="width:92px;">New Era</td>
			<td style="width:128px;">NE-UL5-7&#39;</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">nylon syringe filter, 0.45 um</td>
			<td style="width:92px;">VWR</td>
			<td style="width:128px;">28143-240</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">glovebox</td>
			<td style="width:92px;">Mbraun</td>
			<td style="width:128px;">LABstar</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">solvent purification system</td>
			<td style="width:92px;">Mbraun</td>
			<td style="width:128px;">MB-SPS-800</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">stirplate</td>
			<td style="width:92px;">IKA</td>
			<td style="width:128px;">3582401</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="84">
			<td height="84" style="height:84px;width:205px;">light-emitting diodes</td>
			<td style="width:92px;">Creative Lighting Solutions</td>
			<td style="width:128px;">CL-FRS1210-5M-12V-WH</td>
			<td style="width:147px;">2x 12-inch strips of 5500 K white LEDs were used for illumination</td>
		</tr>
		<tr height="63">
			<td height="63" style="height:63px;width:205px;">12V DC power supply for LEDs</td>
			<td style="width:92px;">Creative Lighting Solutions</td>
			<td style="width:128px;">CL-PS16001-40W</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:205px;">high performance liquid chromatograph&#160;</td>
			<td style="width:92px;">Agilent</td>
			<td style="width:128px;">G1310B, G1322A, G1329B, G1316A</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:205px;">gel permeation size-exclusion columns</td>
			<td style="width:92px;">Agilent</td>
			<td style="width:128px;">PL1110-6500</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="42">
			<td height="42" style="height:42px;width:205px;">multi-angle light scattering detector</td>
			<td style="width:92px;">Wyatt</td>
			<td style="width:128px;">WTREOS</td>
			<td style="width:147px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:205px;">differential refractometer</td>
			<td style="width:92px;">Wyatt</td>
			<td style="width:128px;">WTREX</td>
			<td style="width:147px;"></td>
		</tr>
	</tbody>
</table>

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.

Table 1 shows the range of polymerization results achievable through this method. These data show that perylene is capable of serving as a photocatalyst for the polymerization of a number of functionalized vinyl monomers. For a specific monomer, adjustment of any of a number of reaction parameters such as solvent, stoichiometry, initiator, and light source leads to polymers with varying molecular weights and dispersities ranging from very good to rather broad. Fig...

Watch this Scientific Journal Video about Atom Transfer Radical Polymerization of Functionalized Vinyl Monomers Using Perylene as a Visible Light Photocatalyst at JoVE.com

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

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

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

The overall goal of this procedure is to produce well-defined polymethyl methacrylate using perylene as a visible light photocatalyst for atom transfer radical polymerization. The overall goal of this procedure is to produce well-defined polymethyl methacrylate using perylene as an organic photocatalyst for atom transfer radical polymerization. This method can help answer key questions in the field of organic catalysis and photoredox catalysis such as, can we replace transition metal complexes with organic dyes such as perylene?The main advantage of this technique is that the metal catalyst commonly used in atom transfer radical polymerization can be replaced with perylene, a common organic dye. Visual demonstration of this method is critical to ensure reproducibility among research groups, as the exact reaction setup can have a substantial impact on the outcome of the experiment. Prepare all reagents as described in the text protocol, and allow them to come to room temperature.Inspect all reagents prior to use to ensure there is no sign of contamination such as discoloration or formation of solid particles. In a nitrogen atmosphere glove box, place a small stir bar in a 100 milliliter reaction tube. Add 9.5 milligrams of perylene, and then 4.00 milliliters of dimethylformamide, or DMF.To this mixture, add 4.00 milliliters of methyl methacrylate, or MMA. Place the vial on a stir plate set to 900 rpm inside a 400 milliliter beaker illuminated by strips of white light-emitting diodes. Limit any illumination from other light sources.To initiate the reaction, add 65.6 microliters of ethyl alpha-bromophenylacetate, or EBP, via pipette. Stir the reaction for twenty-four hours under constant illumination. On the bench top, dispense 0.70 milliliters of the butylated hydroxytoluene, or BHT, in deuterated chloroform solution into a two milliliter vial, and seal with a septum cap.Bring this vial into the glove box where the polymerization is being performed. Use a syringe to remove 0.20 milliliters of the reaction mixture. Inject the contents of the syringe into the two milliliter vial containing the 250 ppm solution of BHT and deuterated chloroform.Draw back and push in the plunger several times to ensure thorough quenching of the polymerization. Next, transfer the contents of the two milliliter vial to an NMR spectroscopy tube. Analyze this sample via proton NMR spectroscopy for percent conversion.After analysis, pour the contents of the NMR spectroscopy tube into a clean 20 milliliter scintillation vial. Evaporate the solvent under reduced pressure. Then, redissolve the sample in 1.00 milliliters of tetrahydrofuran.Send the sample through a 0.45 micron syringe filter into a clean two milliliter vial. Analyze the sample via gel permeation chromatography, or GPC, coupled with multi-angle light scattering, to determine number average molecular weight, weight average molecular weight, and dispersity. To isolate and purify the product polymethyl methacrylate, first quench the polymerization reaction by pouring the contents of the reaction mixture into a fifty-fold excess of methanol and letting stir for at least one hour.Isolate the polymethyl methacrylate from the methanol by vacuum filtration. Then, rinse the polymer with an additional 100 milliliters of methanol. Redissolve the polymer in dichloromethane and repeat these steps twice.In a nitrogen atmosphere glove box, place 544 milligrams of polymethyl methacrylate macroinitiator into a 20 milliliter scintillation vial fitted with a small stir bar. Next, add 2.4 milligrams of perylene to the scintillation vial followed by 4.00 milliliters of dimethylformamide. Place the vial on a stir plate set to 900 rpm inside a beaker illuminated by strips of white LEDs.Limit any illumination from other light sources. To this mixture, add 4.96 milliliters of styrene via pipette and stir the reaction for twenty-four hours under constant illumination. Finally, isolate and purify the polymethyl methacrylate block polystyrene product, as before.Shown here are representative results of the polymerization of functionalized vinyl monomers using this technique. Tuning of reaction parameters can have a significant effect on the outcome of the polymerization. This figure shows the results of block copolymerization using an isolated polymethyl methacrylate macroinitiator, as described in the video procedure.The ability to chain extend in this fashion lends support to an atom transfer mechanism. After watching this video, you should have a working understanding of how to produce and isolate well-defined polymers and block copolymers using perylene as a visible light photocatalyst for atom transfer radical polymerization.

Research

Education

JoVE Journal

JoVE Core

Organic Chemistry

Chemistry

Unit 1

Reactions of Alkenes

SCIENTISTS IN ACTION

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 ...

Synthesis and Characterization of Functionalized Metal-organic Frameworks

Metal-organic frameworks have attracted extraordinary amounts of research attention, as they are attractive candidates for numerous industrial and ...

Real-time Monitoring of Reactions Performed Using Continuous-flow Processing: The Preparation of 3-Acetylcoumarin as an Example

By using inline monitoring, it is possible to optimize reactions performed using continuous-flow processing in a simple and rapid way. It is also possible ...

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

Using Polystyrene-block-polyacrylic 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 ...

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 ...

Development of a Backbone Cyclic Peptide Library as Potential Antiparasitic Therapeutics Using Microwave Irradiation

Protein-protein interactions (PPIs) are intimately involved in almost all biological processes and are linked to many human diseases. Therefore, there is ...

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 ...

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 ...

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

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