TY - JOUR A1 - Qian, H. A1 - Kalinka, Gerhard A1 - Chan, K.L.A. A1 - Kazarian, S.G. A1 - Greenhalgh, E.S. A1 - Bismarck, A. A1 - Shaffer, M.S.P. T1 - Mapping local microstructure and mechanical performance around carbon nanotube grafted silica fibres: Methodologies for hierarchical composites N2 - The introduction of carbon nanotubes (CNTs) modifies bulk polymer properties, depending on intrinsic quality, dispersion, alignment, interfacial chemistry and mechanical properties of the nanofiller. These effects can be exploited to enhance the matrices of conventional microscale fibre-reinforced polymer composites, by using primary reinforcing fibres grafted with CNTs. This paper presents a methodology that combines atomic force microscopy, polarised Raman spectroscopy, and nanoindentation techniques, to study the distribution, alignment and orientation of CNTs in the vicinity of epoxy-embedded micrometre-scale silica fibres, as well as, the resulting local mechanical properties of the matrix. Raman maps of key features in the CNT spectra clearly show the CNT distribution and orientation, including a ‘parted’ morphology associated with long grafted CNTs. The hardness and indentation modulus of the epoxy matrix were improved locally by 28% and 24%, respectively, due to the reinforcing effects of CNTs. Moreover, a slower stress relaxation was observed in the epoxy region containing CNTs, which may be due to restricted molecular mobility of the matrix. The proposed methodology is likely to be relevant to further studies of nanocomposites and hierarchical composites. KW - Nanotubes KW - Silica fibres KW - Nano indentation KW - Mapping PY - 2011 U6 - https://doi.org/10.1039/c1nr10497g SN - 2040-3364 SN - 2040-3372 VL - 3 IS - 11 SP - 4759 EP - 4767 PB - RSC Publ. CY - Cambridge AN - OPUS4-34718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -