Synhesis and characterization of AN-VIM-STY

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Sairaj SajjathSamsuddin Faisal Mahmood and

Dr. Dennis W. Smith, Jr.August 20, 2013

Synthesis and characterization of poly (acrylonitrile-co-N-vinylimidazole-co-

styrene) (AN-VIM-Sty) terpolymer

Polymer: Large molecule composed of many subunits (monomers)

Free radical polymerization

AN-VIM copolymerC + N

N

AIBN, 70 °C

DMF CN

N

N

x y z

N

AN VIM

Scheme 1. The synthesis of Poly(acrylonitrile-1-vinylimazole) with AIBN as the initiator and in a DMF solvent system1.

Monomer feed ratio (mol), AN:VIM = 82:18

Tg = 114°CMn = 34,000 Da

Thermal degradation temp = 310°CChar. Yield = 55%Melt processable

Deng, W., Lobovsky, A., Iacono, S. T., Wu, T., Tomar, N., Budy, S. M., Long, T., Hoffman, W. P., Smith Jr, D. W.; Polymer. 52 (2011), 622-628.

Deng, W., Lobovsky, A., Iacono, S. T., Wu, T., Tomar, N., Budy, S. M., Long, T., Hoffman, W. P., Smith Jr, D. W.; Polymer. 52 (2011), 622-628.

Figure 2. AN/VIM polymer in enhanced wound healing.

Figure 3. Application of AN-VIM

as Supercapacitors.

Figure 1. Photographs of AN/VIM polymer as a carbon fiber precursor.

Melt processable carbon fiber precursor

Nitric oxide releasing enhanced wound healing suture Supercapacitors

AN-VIM polymers

In collaboration with Dr. Balkus Group, Alysia

In collaboration with the Dr. Ferraris Group, Kyung-Hye Jung

Jung K.-H., Deng w., Smith Jr., D.W. and Ferraris, J.P., Electrochemistry Communications, 2012, 149-152.

Lowe, A., Deng, W., Smith Jr, D. W., Balkus Jr, K. J., In Press Macromolecules. 2012, 45, 5894-5900.

StyrenePopular feedstock for rubber

Widely used in polymer composites

Economical; clear

Acrylonitrile-styrene (SAN) copolymer

+ Combines properties of acrylonitrile and styrene

New terpolymer synthesis

Scheme 2. The synthesis of Poly(acrylonitrile-co-N-vinylimazole-co-styrene).

Monomer feed ratio (mol), AN:VIM:STY = 80:15:5

Initiator, AIBN = 0.25 mol% of monomers.Reaction Time 48 h.

AN VIM STY

Acrylonitrile + Vinylimidazole + Styrene + AIBN + DMF mixed together and poured drop wise

Over head stirrer

Condenser

Nitrogen

Hot plate

Temp. control probe

Typical reaction setup for synthesis:

Fig : Reaction setup for solvent (DMF) based synthesis

After 48 hr of reaction the reaction mixtureIs taken for precipitation and washing.

Precipitation and working up the polymer

Precipitation in DI water Washing with excess DI water Decant

Washing with EthanolDecant

Washing with HexaneDecantDrying in Vacuum

Oven

Figure: Flowchart for polymer precipitation and work up of AN-VIM-Sty co polymer.

1 3, 4,5,6,27 8,9

10, 11, 12

H2O

DMSO-d6

Molar Feed Ration: AN:VIM:STY = 80:15:5Polymer composition by NMR: AN:VIM:STY = 80.5:14.5:5.0

NMR Spectrum of acrylonitrile-co-N-vinylimidazole-co-styrene terpolymer.

3113 cm-1 ring stretching, 2916 cm-1 (backbone CH2 stretching, asymmetrical), 2850 cm-1 CH2 stretching symmetrical, 2241 cm-1 (CN stretching), 1230 cm-1

(C-N ring stretching), 1083 cm-1 (C-H ring in-phase bending) and 667 cm-1 (imidazole ring bending), 1450 cm-1 (CH2 bending of backbone), 744 cm-1 out of plane aromatic bend, 705 cm-1 ring C=C bend.

ATR-FTIR Spectrum of acrylonitrile-co-N-vinylimidazole-co-styrene terpolymer.

TGA in N2, Td 310 C

Thermal Analysis: TGA

Thermal Analysis: TGA

TGA in Air

Char Yield, 44%

00

Thermal Analysis: TGA

Thermal Analysis: DSC

DSC Thermogram, Tg 114 C

Scheme 2. The synthesis of Poly(acrylonitrile-co-N-vinylimazole-co-styrene).

Monomer feed ratio (mol), AN:VIM:Sty = 80:15:5

Tg = 114°CThermal degradation temp = 310°C

Char. Yield = 44%Melt processable

AN-VIM-Sty Terpolymer

Alan G. MacDiarmid NanoTech Institute Dr. Dennis W. Smith, Jr.

Samsuddin Faisal Mahmood

All the group members Welch Foundation and CEHMS.

Acknowledgements