Microstructure and macroscopic properties of hybrid carbon nanofiber/silica fume cement composites

Abstract The effect of up to 2 wt% of “as received” carbon nanofiber (CNF) loading on the microstructural, physical, and mechanical (compressive and splitting tensile strengths) properties of hybrid CNF/silica fume cement composites has been studied. Silica fume (SF) facilitated CNF dispersion due to its small particle size and improved the interfacial interaction between the CNFs and the cement phases. The CNFs were found embedded as individual fibers throughout the paste and self-aggregated as clumps in pockets. Mechanically, the CNFs embedded in the paste and at the pocket edges acted to offset the effect of defects created by the pockets. The addition of CNFs promoted pore refinement of the composites and increased the pore volume in the 6–200 nm pore diameter range, ascribed in part to interstitial pores between the entangled CNFs.

[1]  Yiu-Wing Mai,et al.  Dispersion and alignment of carbon nanotubes in polymer matrix: A review , 2005 .

[2]  J. Luh,et al.  CARBON NANOTUBE/CEMENT COMPOSITES - EARLY RESULTS AND POTENTIAL APPLICATIONS , 2005 .

[3]  James J. Beaudoin,et al.  Carbon Nanotubes and their Application in the Construction Industry , 2004 .

[4]  A. Neville.  Properties of Concrete , 1968 .

[5]  H. Toutanji,et al.  Chloride permeability and impact resistance of polypropylene-fiber-reinforced silica fume concrete , 1998 .

[6]  Sidney Diamond,et al.  Densified silica fume: particle sizes and dispersion in concrete , 2006 .

[7]  D. Chung.  Dispersion of Short Fibers in Cement , 2005 .

[8]  Edurne Erkizia,et al.  Atomic force microscopy and nanoindentation of cement pastes with nanotube dispersions , 2006 .

[9]  Edward J. Garboczi,et al.  Smart and designer structural material systems , 2002 .

[10]  Thomas O. Mason,et al.  AC-impedance response of multi-walled carbon nanotube/cement composites , 2006 .

[11]  K. N. Pandey,et al.  Study on mechanical, morphological and electrical properties of carbon nanofiber/polyetherimide composites , 2007 .

[12]  J. Dolado,et al.  High-Performance Nanostructured Materials for Construction , 2004 .

[13]  E. Barrett,et al.  The Determination of Pore Volume and Area Distributions in Porous Substances. II. Comparison between Nitrogen Isotherm and Mercury Porosimeter Methods , 1951 .

[14]  D. Roy,et al.  AN INVESTIGATION OF THE EFFECT OF ORGANIC SOLVENT ON THE RHEOLOGICAL PROPERTIES AND HYDRATION OF CEMENT PASTE , 1987 .

[15]  Xiaohua Zhao,et al.  Mechanical behavior and microstructure of cement composites incorporating surface-treated multi-walled carbon nanotubes , 2005 .

[16]  E. Barrett,et al.  (CONTRIBUTION FROM THE MULTIPLE FELLOWSHIP OF BAUGH AND SONS COMPANY, MELLOX INSTITUTE) The Determination of Pore Volume and Area Distributions in Porous Substances. I. Computations from Nitrogen Isotherms , 1951 .

[17]  V. Shanov,et al.  Introduction to carbon nanotube and nanofiber smart materials , 2006 .

[18]  D.D.L. Chung,et al.  Review: Improving cement-based materials by using silica fume , 2002 .

[19]  Maria C.G. Juenger,et al.  ALKALI-SILICA REACTIVITY OF LARGE SILICA FUME-DERIVED PARTICLES , 2004 .

[20]  Dale P. Bentz,et al.  Influence of silica fume on diffusivity in cement-based materials: I. Experimental and computer modeling studies on cement pastes , 2000 .

[21]  P. Pötschke,et al.  Carbon nanofibers for composite applications , 2004 .

[22]  D. Chung.  Comparison of submicron-diameter carbon filaments and conventional carbon fibers as fillers in composite materials , 2001 .

[23]  Sidney Diamond,et al.  Reaction products of densified silica fume agglomerates in concrete , 2004 .

[24]  Xiaohua Zhao,et al.  Pressure-sensitive properties and microstructure of carbon nanotube reinforced cement composites , 2007 .