Publication Images

Notched Izod impact strength of PP/MWNT nanocomposites prepared from PP/f-MWNT master batch.

S. Ghoshal, P. -H. Wang, P. Gulgunje, N. Verghese, S. Kumar, “High impact strength polypropylene containing carbon nanotubes”, Polymer (2016). 100, 259-274.


Schematic illustration of MWNT functionalization, master batch and nanocomposite preparation. (a) p-MWNT was treated with 10 M HNO3 at 120 °C for 24 h (b) f-MWNT was sonicated in butanol for 48 h after which MA-g-PP/xylene or PP/xylene solution was added drop-by-drop into the f-MWNT/butanol dispersion at 60 °C followed by drying. (c) f-MWNT master batch was physically mixed with PP. The mixture was then micro-compounded and injection molded.

TEM images of (a,b) PP/f-MWNT and (c,d) MA-g-PP/f-MWNT master batches. Both PP and MA-g-PP form continuous coating on f-MWNTs, suggesting interaction between nanotubes and the polymers. There appears to be no gap between polymer and f-MWNTs. Images (a) and (c) as well as the arrow in (b) demonstrates the ability of polymer coating on separating vicinity MWNTs.

P. -H. Wang, S. Ghoshal, P. Gulgunje, N. Verghese, S. Kumar, “Polypropylene nanocomposites with polymer coated multiwall carbon nanotubes”. Polymer (2016), 100, 244-258


Tensile strength versus tensile modulus of various PAN based carbon fibers. ...

Figure 1. Tensile strength versus tensile modulus of various PAN based carbon fibers. Circles represent the tensile properties of commercial PAN based carbon fibers. Stars represent the tensile strength and modulus of the GT PAN based carbon fibers produced under DARPA ASF program. Trend lines 1 and 2 represent trajectory of the developments in the high strength and high modulus solution spun PAN based carbon fibers, respectively over the last 30 years. Trend line 3 represents the development trajectory in gel spun PAN based carbon fiber under DARPA ASF program

H. G. Chae, B. A. Newcomb, P. V. Gulgunje, Y. Liu, K. Gupta, M. G. Kamath, K. M. Lyons, S. Ghoshal, C. Pramanik, L. A. Giannuzzi, K. Sahin, I. Chasiotis, S. Kumar, “High strength and high modulus carbon fibers”, Carbon, 93, 81-87 (2015). http://dx.doi.org/10.1016/j.carbon.2015.05.016.


B. A. Newcomb, L. A. Giannuzzi, K. M. Lyons, P. V. Gulgunje, K. Gupta, Y. Liu, M. G. Kamath, K. McDonald, J. Moon, B. Feng, G. P. Peterson, H. G. Chae, S. Kumar, “High resolution transmission electron microscopy study on polyacrylonitrile/carbon nanotube based carbon fibers and the effect of structure development on the thermal and electrical conductivities”, Carbon, 93, 502-514 (2015). http://dx.doi.org/10.1016/j.carbon.2015.05.037.


b) SEM micrograph of hollow carbon fiber with honecycomb cross-section, d) Raman G band intensity variation across the fiber cross section.

P. V. Gulgunje, B. A. Newcomb, K. Gupta, H. G. Chae, T. Tsotsis, S. Kumar, “Low density and high-modulus carbon fibers from polyacrylonitrile with honeycomb structure”, Carbon,95, 710-714 (2015). DOI: 10.1016/j.carbon.2015.08.097.


P. V. Gulgunje, B. A. Newcomb, K. Gupta, H. G. Chae, T. Tsotsis, S. Kumar, “Low density and high-modulus carbon fibers from polyacrylonitrile with honeycomb structure”, Carbon, 95, 710-714 (2015). DOI: 10.1016/j.carbon.2015.08.097.


B. A. Newcomb, L. A. Giannuzzi, K. M. Lyons, P. V. Gulgunje, K. Gupta, Y. Liu, M. G. Kamath, K. McDonald, J. Moon, B. Feng, G. P. Peterson, H. G. Chae, S. Kumar, “High resolution transmission electron microscopy study on polyacrylonitrile/carbon nanotube based carbon fibers and the effect of structure development on the thermal and electrical conductivities”, Carbon, 93, 502-514 (2015). http://dx.doi.org/10.1016/j.carbon.2015.05.037.


K. Sahin, N. A. Fasanella, I. Chasiotis, K. M. Lyons, B. A. Newcomb, M. G. Kamath, H. G. Chae, S. Kumar, “High Strength Micron Size Carbon Fibers from PAN-CNT Precursors”, Carbon, 77, p. 442 – 453 (2014). DOI: 10.1016/j.carbon.2014.05.049.


H. Clive Liu, A. T. Chien, B. A. Newcomb, Y. Liu, S. Kumar, “Processing, structure and properties of lignin and CNT incorporated PAN based carbon fibers”, ACS Sustainable Chemistry and Engineering, (2015). http://dx.doi.org/10.1021/acssuschemeng.5b00562.


A. A. B. Davijani and S. Kumar, “Ordered wrapping of poly (methyl methacrylate) on single wall carbon nanotubes, Polymer,70, 278-281 (2015). http://dx.doi.org/10.1016/j.polymer.2015.06.018.


Abstract Image

Tensile modulus of PAN and PAN/CNC composite fibers.

H. Chang, A. T. Chien, H. C. Liu, P. H. Wang, B. A. Newcomb, and S. Kumar, “Gel Spinning of Polyacrylonitrile/Cellulose Nanocrystal Composite Fibers”, ACS Biomaterials Science and Engineering, (2015). http://dx.doi.org/10.1021/acsbiomaterials.5b00161.


A. T. Chien, H. C. Liu, B. A. Newcomb, C. Xiang, J. M. Tour, S. Kumar, “PAN fibers containing graphene oxide nanoribbons”, ACS Applied Materials and Interfaces, 7, 5281 - 5288 (2015). DOI:10.1021/am508594p.


A. T. Chien, S. Cho, Y. Joshi, S. Kumar, “Electrical Conductivity and Joule Heating of Polyacrylonitrile/Carbon Nanotube Composite Fibers”, Polymer, 55, p. 6896 – 6905 (2014). DOI: 10.1016/j.polymer.2014.10.064.


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Typical bi-component fiber cross-sections: (a) sheath-core, (b) side-by-side, (c) layer-by-layer, (d) islands-in-the-sea, and (e) segmented pie.

T. Hongu, G. O. Phillips and M. Takigami, New Millennium Fibers. (Cambridge, Woodhead, Boca Raton, 2005)
L. H. Sperlin, In Recent Advances in Polymer Blends, Graft, and Blocks. (Plenum Press, New York, 1974)


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Optical image of PAN sheath – PAN/MWNT core bi-component fibers


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Optical image of PAN/MWNT sheath and PAN core bi-component fibers
An-Ting Chien, Prabhakar V. Gulgunje, Han Gi Chae, Aniruddha Joshi, Jaeyun Moon,
Bo Feng, G. P. Peterson, and Satish Kumar, “Functional Polyacrylonitrile-Polyacrylonitrile/Carbon Nanotube Bi-component Fibers”, SAMPE Technical Conference Proceedings, Charleston SC, October 22-25, 2012.


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Temperature-dependent thermal conductivity of PEK/CNT fibers with diverse CNT loadings
Moon, J.; Weaver, K.; Feng, B.; Chae, H. G.; Kumar, S.; Baek, J.-B.; Peterson, G. P., Thermal conductivity measurement of individual poly(ether ketone)/carbon nanotube fibers using a steady-state dc thermal bridge method. Review of Scientific Instruments 2012, 83 (1).


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Basu-Dutt, S.; Minus, M. L.; Jain, R.; Nepal, D.; Kumar, S., Chemistry of Carbon Nanotubes for Everyone. Journal of Chemical Education 2012, 89 (2), 221-229


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Molecular schematic of (b), possible [1000]/[010] epitaxial matching between PVA chain and graphite sheet, and arrangement of PVA chains with this epitaxial matching on (c) armchair SWNT, (d) zig-zag SWNT, and (e) chiral SWNT.
Minus, M. L.; Chae, H. G.; Kumar, S., Observations on Solution Crystallization of Poly(vinyl alcohol) in the Presence of Single-Wall Carbon Nanotubes. Macromolecular Rapid Communications 2010, 31 (3), 310-316


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SEM images of nanocomposite fibers by solution crystallization. HDPE composites with (a) 2 and (b) 12 hours of crystallization, UHMWPE composites with (c) 2 and (d) 12 hours of crystallization.
Zhang, S.; Lin, W.; Wong, C.-P.; Bucknall, D. G.; Kumar, S., Nanocomposites of Carbon Nanotube Fibers Prepared by Polymer Crystallization. Acs Applied Materials & Interfaces 2010, 2 (6), 1642-1647


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Change in specific capacitance for PAN/CNT films with different compositions measured at 5 mV s-1 scan rate cyclic voltammetry in 6 M KOH for 10,000 cycles.
Jagannathan, S.; Liu, T.; Kumar, S., Pore size control and electrochemical capacitor behavior of chemically activated polyacrylonitrile - Carbon nanotube composite films. Composites Science and Technology 2010, 70 (4), 593-598


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Scanning electron micrographs of SWNT/polyethylene shish-kebab structure at (a) low and (b) high magnifications.
Minus, M. L.; Chae, H. G.; Kumar, S., Polyethylene Crystallization Nucleated by Carbon Nanotubes under Shear. Acs Applied Materials & Interfaces 2012, 4 (1), 326-330


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Storage modulus and tan δ behavior of PMMA, SWNT-A/PMMA (10/90), and SWNT-A (15/85) composite films as a function of temperature
Liu, J.; Rasheed, A.; Minus, M. L.; Kumar, S., Processing and Properties of Carbon Nanotube/Poly(methyl methacrylate) Composite Films. Journal of Applied Polymer Science 2009, 112 (1), 142-156


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Electrical conductivity of SWNT-B/PMMA composites
Liu, J.; Rasheed, A.; Minus, M. L.; Kumar, S., Processing and Properties of Carbon Nanotube/Poly(methyl methacrylate) Composite Films. Journal of Applied Polymer Science 2009, 112 (1), 142-156


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Kim, Y.-t.; Haftel, V. K.; Kumar, S.; Bellamkonda, R. V., The role of aligned polymer fiber-based constructs in the bridging of long peripheral nerve gaps. Biomaterials 2008, 29 (21), 3117-3127


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Solubility of acid treated SWNTs in xylene/butanol mixture. Top and bottom rows indicate amount of xylene and butanol in milliliters, respectively. Acid treated SWNTs (1 mg) were dispersed in 8 mL xylene and sonicated for 30 min and the dispersion was allowed to settle for 2 h before taking a photograph. Subsequently, each time 1.6 mL butanol was added followed by sonication (30 min) and settling (2 h).
Lee, G. W.; Jagannathan, S.; Chae, H. G.; Minus, M. L.; Kumar, S., Carbon nanotube dispersion and exfoliation in polypropylene and structure and properties of the resulting composites. Polymer 2008, 49 (7), 1831-1840


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Shrinkage behavior of polypropylene (PP) and PP/CNT fibers at 3.2 MPa stress.
Lee, G. W.; Jagannathan, S.; Chae, H. G.; Minus, M. L.; Kumar, S., Carbon nanotube dispersion and exfoliation in polypropylene and structure and properties of the resulting composites. Polymer 2008, 49 (7), 1831-1840


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Scanning electron micrograph of vapor grown carbon nanofiber (VGCNF) powder
Guo, H.; Rasheed, A.; Minus, M. L.; Kumar, S., Polyacrylonitrile/vapor grown carbon nanofiber composite films. Journal of Materials Science 2008, 43 (13), 4363-4369


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PMMA cups electrospun from nitromethane solution
Liu, J.; Rasheed, A.; Dong, H.; Carr, W. W.; Dadmun, M. D.; Kumar, S., Electrospun Micro- and Nanostructured Polymer Particles. Macromolecular Chemistry and Physics 2008, 209 (23), 2390-2398


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Chae, H. G.; Kumar, S., Materials science - Making strong fibers. Science 2008, 319 (5865), 908-909


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Optical micrographs of transcrystalline interphases for polypropylene surrounding the CNTs fibers isothermally crystallized at 125 ºC: (a) a single CNT fiber and (b) two CNT fibers.
Zhang, S.; Minus, M. L.; Zhu, L.; Wong, C.-P.; Kumar, S., Polymer transcrystallinity induced by carbon nanotubes. Polymer 2008, 49 (5), 1356-1364


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Scanning electron micrographs of twisted fibers with densification: (a) single fiber; (b) nanotube arrangement in the fiber; (c) nanotube fiber knot, and (d) double twisted fiber. Arrow shows the direction of the fiber axis.
Zhang, S.; Zhu, L.; Minus, M. L.; Chae, H. G.; Jagannathan, S.; Wong, C.-P.; Kowalik, J.; Roberson, L. B.; Kumar, S., Solid-state spun fibers and yarns from 1-mm long carbon nanotube forests synthesized by water-assisted chemical vapor deposition. Journal of Materials Science 2008, 43 (13), 4356-4362


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Porous fibers from solution of iPMMA in methylene chloride at different magnifications
Dayal, P.; Liu, J.; Kumar, S.; Kyu, T., Experimental and theoretical investigations of porous structure formation in electrospun fibers. Macromolecules 2007, 40 (21), 7689-7694


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Porous fibers from aPMMA/MC.
Dayal, P.; Liu, J.; Kumar, S.; Kyu, T., Experimental and theoretical investigations of porous structure formation in electrospun fibers. Macromolecules 2007, 40 (21), 7689-7694


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(a) Porous fibers from PS/THF. (b) Magnification of the fiber surface features in a.
Dayal, P.; Liu, J.; Kumar, S.; Kyu, T., Experimental and theoretical investigations of porous structure formation in electrospun fibers. Macromolecules 2007, 40 (21), 7689-7694


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SEM micrographs of (a) stabilized PAN and (b) stabilized PAN/SWNT (99/1), (c) carbonized PAN and (d) carbonized PAN/SWNT (99/1) fibers.
Chae, H. G.; Minus, M. L.; Rasheed, A.; Kumar, S., Stabilization and carbonization of gel spun polyacrylonitrile/single wall carbon nanotube composite fibers. Polymer 2007, 48 (13), 3781-3789


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Transmission electron micrographs of the single-layer carbon nano fibers
Uchida, T.; Anderson, D. P.; Minus, M. L.; Kumar, S., Morphology and modulus of vapor grown carbon nano fibers. Journal of Materials Science 2006, 41 (18), 5851-5856


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Current-voltage plots of SWNTs and pyrrole treated arylsulfonic acid-functionalized SWNTs at a scan rate of 10 mV/s
Zhou, C. F.; Kumar, S.; Doyle, C. D.; Tour, J. M., Functionalized single wall carbon nanotubes treated with pyrrole for electrochemical supercapacitor membranes. Chemistry of Materials 2005, 17 (8), 1997-2002


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(a) High-resolution transmission electron micrograph of the electrospun PAN/SWNT composite fiber and (b, c, and d) scanning electron micrographs of electrospun SWNT/PMMA fibers
Liu, J.; Wang, T.; Uchida, T.; Kumar, S., Carbon nanotube core-polymer shell nanofibers. Journal of Applied Polymer Science 2005, 96 (5), 1992-1995


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Electroprocessed PMMA cup
Liu, J.; Kumar, S., Microscopic polymer cups by electrospinning. Polymer 2005, 46 (10), 3211-3214


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Storage modulus and tan δ behavior of PAN and PAN/SWNT film as a function of temperature
Guo, H.; Sreekumar, T. V.; Liu, T.; Minus, M.; Kumar, S., Structure and properties of polyacrylonitrile/single wall carbon nanotube composite films. Polymer 2005, 46 (9), 3001-3005


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Thermal expansion of PAN and PAN/SWNT (60/40) films as a function of temperature
Guo, H.; Sreekumar, T. V.; Liu, T.; Minus, M.; Kumar, S., Structure and properties of polyacrylonitrile/single wall carbon nanotube composite films. Polymer 2005, 46 (9), 3001-3005


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Scanning electron micrographs of (a) SWNT powder and (b) PAN/SWNT (60/40) film
Guo, H.; Sreekumar, T. V.; Liu, T.; Minus, M.; Kumar, S., Structure and properties of polyacrylonitrile/single wall carbon nanotube composite films. Polymer 2005, 46 (9), 3001-3005


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Transmission electron micrograph of carbon nanofibers
Uchida, T.; Dang, T.; Min, B. G.; Zhang, X. F.; Kumar, S., Processing, structure, and properties of carbon nano fiber filled PBZT composite fiber. Composites Part B-Engineering 2005, 36 (3), 183-187


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Dynamic mechanical properties of poly(ethylene terephthalate) (PET) and PET/POSS composite fibers. (a) Storage modulus and (b) tan δ behavior as a function of temperature
Zeng, J.; Kumar, S.; Iyer, S.; Schiraldi, D. A.; Gonzalez, R. I., Reinforcement of poly(ethylene terephthalate) fibers with polyhedral oligomeric silsesquioxanes (POSS). High Performance Polymers 2005, 17 (3), 403-424


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G’ band shift in the PMMA/SWNT composites as a function of Δδp
Liu, J.; Liu, T.; Kumar, S., Effect of solvent solubility parameter on SWNT dispersion in PMMA. Polymer 2005, 46 (10), 3419-3424


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Radial breathing mode (RBM) bands of SWNT powder and PMMA/SWNT composite films made from toluene and nitromethane. Dotted lines show Lorentzian peak fitting to the SWNT powder spectra
Liu, J.; Liu, T.; Kumar, S., Effect of solvent solubility parameter on SWNT dispersion in PMMA. Polymer 2005, 46 (10), 3419-3424


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Transmission electron micrographs of (b) and (c) individual SWNTs in the PAN/SWNT (95/5) composites.
Uchida, T.; Kumar, S., Single wall carbon nanotube dispersion and exfoliation in polymers. Journal of Applied Polymer Science 2005, 98 (3), 985-989


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WAXD meridional scans of poly(ethylene terephthalate-co-4,4’-bibenzoate)
Ma, H. M.; Uchida, T.; Collard, D. M.; Schiraldi, D. A.; Kumar, S., Crystal structure and composition of poly(ethylene terephthalate-co-4,4 '-bibenzoate). Macromolecules 2004, 37 (20), 7643-7648


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FTIR spectra of 6 M HNO3 treated SWNT with and without KOH wash


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d spacing of SWNT diffraction peaks in films processed from nitric acid and heat treated at 900 ºC. Diffraction plane (a) (1,0) and (b) (1,1)

Zhang, X. F.; Sreekumar, T.V.; Liu, T.; Kumar, S., Properties and structure of nitric acid oxidized single wall carbon nanotube films. Journal of Physical Chemistry B 2004, 108 (42), 16435-16440


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(a) Tan δ and (b) storage modulus as a function of temperature for PAN and PAN/SWNT composite fibers (Note: In figure 1b (storage modulus vs temperature), the storage plots have been labeled incorrectly. The plot marked as PAN/SWNT (90/10) should read PAN/SWNT (95/5), and the plot marked PAN/SWNT (95/5) should read PAN/SWNT (90/10).)
Sreekumar, T. V.; Liu, T.; Min, B. G.; Guo, H.; Kumar, S.; Hauge, R. H.; Smalley, R. E., Polyacrylonitrile single-walled carbon nanotube composite fibers. Advanced Materials 2004, 16 (1), 58-61


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Polarized infrared spectra of PAN and PAN/SWNT (99/1) composite fibers.
Sreekumar, T. V.; Liu, T.; Min, B. G.; Guo, H.; Kumar, S.; Hauge, R. H.; Smalley, R. E., Polyacrylonitrile single-walled carbon nanotube composite fibers. Advanced Materials 2004, 16 (1), 58-61


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The half-time of crystallization, t1/2, of the PET/PETBB55 (70/30) blend as a function of isothermal crystallization temperature
Min, B.; Kumar, S.; Hibbs, M. R.; Ma, H. M.; Collard, D. M.; Schiraldi, D. A., Sequence analysis and fiber properties of a blend of poly(ethylene terephthalate) and poly(ethylene terephthalate-co-4,4 '-bibenzoate). Journal of Applied Polymer Science 2004, 93 (4), 1793-1803


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Scanning electron micrographs of (a) as-produced HiPCO SWNT powder, and (b) as-produced SWNT/PAN composite films
Liu, T.; Sreekumar, T. V.; Kumar, S.; Hauge, R. H.; Smalley, R. E., SWNT/PAN composite film-based supercapacitors. Carbon 2003, 41 (12), 2440-2442


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Specific capacitance as a function of discharging voltage for SWNT/activated carbon and SWNT/ bucky paper at different constant discharging currents
Liu, T.; Sreekumar, T. V.; Kumar, S.; Hauge, R. H.; Smalley, R. E., SWNT/PAN composite film-based supercapacitors. Carbon 2003, 41 (12), 2440-2442


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Scanning electron micrograph of PET/CNF (PET/PR-24-HT) composite
Ma, H. M.; Zeng, J. J.; Realff, M. L.; Kumar, S.; Schiraldi, D. A., Processing, structure, and properties of fibers from polyester/carbon nanofiber composites. Composites Science and Technology 2003, 63 (11), 1617-1628


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Stress-strain curves for PVA, PVA/PVP/SDS, and PVA/PVP/SDS/SWNT films. SWNT content is 5 wt % of the PVA/PVP/SDS/SWNT film
Zhang, X. F.; Liu, T.; Sreekumar, T. V.; Kumar, S.; Moore, V. C.; Hauge, R. H.; Smalley, R. E., Poly(vinyl alcohol)/SWNT composite film. Nano Letters 2003, 3 (9), 1285-1288


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Raman D* band peak position as a function of strain for PVA/PVP/SDS/SWNT composite films containing 5 wt % SWNT.
Zhang, X. F.; Liu, T.; Sreekumar, T. V.; Kumar, S.; Moore, V. C.; Hauge, R. H.; Smalley, R. E., Poly(vinyl alcohol)/SWNT composite film. Nano Letters 2003, 3 (9), 1285-1288


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Scanning electron micrograph of SWNT film
Sreekumar, T. V.; Liu, T.; Kumar, S.; Ericson, L. M.; Hauge, R. H.; Smalley, R. E., Single-wall carbon nanotube films. Chemistry of Materials 2003, 15 (1), 175-178


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Effect of SWNT rope orientation on the modulus of SWNT fiber
Liu, T.; Kumar, S., Effect of orientation on the modulus of SWNT films and fibers. Nano Letters 2003, 3 (5), 647-650.


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Structure of (top) PBO and (bottom) SWNT

Kumar, S.; Dang, T. D.; Arnold, F. E.; Bhattacharyya, A. R.; Min, B. G.; Zhang, X. F.; Vaia, R. A.; Park, C.; Adams, W. W.; Hauge, R. H.; Smalley, R. E.; Ramesh, S.; Willis, P. A., Synthesis, structure, and properties of PBO/SWNT composites. Macromolecules 2002, 35 (24), 9039-9043


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Scanning electron micrograph of fibers from PP/nano carbon fiber composite

Kumar, S.; Doshi, H.; Srinivasarao, M.; Park, J. O.; Schiraldi, D. A., Fibers from polypropylene/nano carbon fiber composites. Polymer 2002, 43 (5), 1701-1703