Dispersion of carbon nanotubes in melt compounded polypropylene based composites investigated by THz spectroscopy.

We investigate the use of Terahertz (THz) Time Domain Spectroscopy (TDS) as a tool for the measurement of the index dispersion of multi-walled carbon nanotubes (MWCNT) in polypropylene (PP) based composites. Samples containing 0.5% by volume concentration of non-functionalized and functionalized carbon nanotubes are prepared by melt compounding technology. Results indicate that the THz response of the investigated nanocomposites is strongly dependent on the kind of nanotube functionalization, which in turn impacts on the level of dispersion inside the polymer matrix. We show that specific dielectric parameters such as the refractive index and the absorption coefficient measured by THz spectroscopy can be both correlated to the index of dispersion as estimated using conventional optical microscopy.

[1]  Lin Li,et al.  POLYMER NANOCOMPOSITES BASED ON FUNCTIONALIZED CARBON NANOTUBES , 2010 .

[2]  Yun-Sik Jin,et al.  Terahertz Dielectric Properties of Polymers , 2006 .

[3]  Petra Pötschke,et al.  Dispersion, agglomeration, and network formation of multiwalled carbon nanotubes in polycarbonate melts , 2008 .

[4]  M. Koch,et al.  Determination of additive content in polymeric compounds with terahertz time-domain spectroscopy , 2007 .

[5]  M. Reuter,et al.  Terahertz time-domain spectroscopy as a tool to monitor the glass transition in polymers. , 2009, Optics express.

[6]  Martin Koch,et al.  Terahertz spectroscopy on polymers: A review of morphological studies , 2011 .

[7]  Jianguo Tian,et al.  Optical limiting effect and ultrafast saturable absorption in a solid PMMA composite containing porphyrin-covalently functionalized multi-walled carbon nanotubes. , 2013, Optics express.

[8]  W. Bauhofer,et al.  A review and analysis of electrical percolation in carbon nanotube polymer composites , 2009 .

[9]  N. A. Siddiqui,et al.  DISPERSION AND FUNCTIONALIZATION OF CARBON NANOTUBES FOR POLYMER-BASED NANOCOMPOSITES: A REVIEW , 2010 .

[10]  Amos Martinez,et al.  Fabrication of Carbon nanotube poly-methyl-methacrylate composites for nonlinear photonic devices. , 2008, Optics express.

[11]  C. Megaridis,et al.  Terahertz shielding of carbon nanomaterials and their composites – A review and applications , 2014 .

[12]  Martin Koch,et al.  Degree of dispersion of polymeric compounds determined with terahertz time‐domain spectroscopy , 2011 .

[13]  Snyder,et al.  Geometrical percolation threshold of overlapping ellipsoids. , 1995, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics.

[14]  L. Flandin,et al.  Optical density as a probe of carbon nanotubes dispersion in polymers , 2013 .

[15]  P. Pötschke,et al.  Influence of small scale melt mixing conditions on electrical resistivity of carbon nanotube-polyamide composites , 2009 .

[16]  H. Altan,et al.  Characterization of polypropylene treated under dual-RF plasma using terahertz time-domain spectroscopy , 2013, Journal of Materials Science.

[17]  Jeffrey W. Gilman,et al.  Characterization of Polymer-Layered Silicate (Clay) Nanocomposites by Transmission Electron Microscopy and X-Ray Diffraction: A Comparative Study , 2003 .

[18]  M. Koch,et al.  TERAHERTZ QUALITY CONTROL OF POLYMERIC PRODUCTS , 2007 .

[19]  M. Reuter,et al.  Investigating Material Characteristics and Morphology of Polymers Using Terahertz Technologies , 2013, IEEE Transactions on Terahertz Science and Technology.

[20]  Jean-Louis Coutaz,et al.  Precise Determination of the Refractive Index of Samples Showing Low Transmission Bands by THz Time-Domain Spectroscopy , 2013, IEEE Transactions on Terahertz Science and Technology.

[21]  Wolfgang Bauhofer,et al.  A review and analysis of electrical percolation in carbon nanotube polymer composites , 2009 .

[22]  M. Nathan,et al.  Saturable absorption of multi-walled carbon nanotubes/hybrid-glass composites , 2012 .

[23]  Christopher W. Macosko,et al.  Linear low density polyethylene (LLDPE)/clay nanocomposites. Part I: Structural characterization and quantifying clay dispersion by melt rheology , 2007 .

[24]  M. Cakmak,et al.  The role of plasticizer on the exfoliation and dispersion and fracture behavior of clay particles in PVC matrix: a comprehensive morphological study , 2004 .

[25]  H. Wagner,et al.  The role of surfactants in dispersion of carbon nanotubes. , 2006, Advances in colloid and interface science.

[26]  K. Minoshima,et al.  Ultrashort pulse-generation by saturable absorber mirrors based on polymer-embedded carbon nanotubes. , 2005, Optics express.

[27]  A. Skordos,et al.  Monitoring dispersion of carbon nanotubes in a thermosetting polyester resin , 2009 .

[28]  Amos Martinez,et al.  Carbon nanotube/polymer composite coated tapered fiber for four wave mixing based wavelength conversion. , 2013, Optics express.

[29]  Determination of the Carbon Nanotube Concentration and Homogeneity in Resin Films by THz Spectroscopy and Imaging , 2012 .

[30]  M. Koch,et al.  Highly accurate optical material parameter determination with THz time-domain spectroscopy. , 2007, Optics express.

[31]  M. Cazayous,et al.  High-Crystalline Single- and Double-Walled Carbon Nanotube Mats Grown by Chemical Vapor Deposition , 2007 .

[32]  N. Vieweg,et al.  Monitoring polymeric compounding processes inline with THz time-domain spectroscopy , 2009 .