The cluster architecture of carbon in polymer nanocomposites observed by impulse acoustic microscopy

Abstract

physica s s p status solidi b 1956 V. Levin et al.: The cluster architecture of carbon in polymer nanocomposites ß

Cluster microstructure and local elasticity of carbon‐epoxy nanocomposites studied by impulse acoustic microscopy

“…The images are formed in an ultramicroscopic mode —sizes of some scatterers could be smaller than the wavelength; the presence of air in the conglomerates results in a high efficiency of ultrasonic scattering; according to estimations , conglomerates are effective scatterers. It has been revealed that both graphite nanoparticles (GNP) and nanotubes (MWCNT) possess a strong tendency to agglomeration . Depending on the filler content these agglomerates are formed and distributed over the material bulk.…”

“…Impulse acoustic microscopy is based on using focused ultrasonic beams and the raster principle of image formation . A focused ultrasonic beam interacts with a plane‐parallel object within its waist.…”

“…Independent measurement of the material density ρ makes it possible to find elastic modules of the material. The ultrasonic technique is especially attractive in the case of the scanning impulse acoustic microscopy when employing focused ultrasound. Application of focused probe impulses enables one to measure local values of sonic velocities in inhomogeneous specimens with micron resolution and to find spatial distribution of elastic properties over the specimen bulk.…”

Noninvasive ultrasound imaging for assessment of intact microstructure of extracellular matrix in tissue engineering

“…Difficulty of volume imaging of all common methods remains in receiving of low magnitudes or detecting of small differences of signals. Efficiency of ultrasound scattering at small‐size elements depends on acoustic impedance ratio between immersion liquid and scatterer . In the decellularized lung samples, the protein elements without cell content have slightly higher acoustic impedance and amplitude of back‐scattered signal (Table ).…”

“…Experimental setup of SIAM‐2011 is shown in Figure . The method is described in detail in previous works . We used common regime of imaging—C‐scanning which presents internal microstructure in the form of layer‐by‐layer images of horizontal cross‐sections at different depths (Figure ); and modified B/D‐mode (brightness/depth) which images internal microstructure in vertical section.…”