Third Microsymposium of the "International Scholarship Program for Graduate Studies in Faculty of Chemistry, University of Warsaw - From simple molecules to nanostructured and bioactive materials" October 6 - 8th, 2011, Palace in Łochów, Poland
Chronicle
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Thursday Oct. 6th 16:45 - 17:15 – Jerzy Romiszewski Alignment of nanotubes in composites with block copolymer matrices Dependency of alignment of Mo6S2I8 nanotubes in composites on type of block copolymer matrix and on preparation technique was studied. Two types of polymer matrices were used: SEBS block copolymer - forming columnar hexagonal phase and SIS block copolymer - forming micellar phase. Composites were prepared either by melt mixing and extrusion or by precipitation from dispersion. Morphology of polymer matrix was studied by means of SAXS and SEM techniques whereas nanotubes orientation was deduced from linear dichroism measurements. Comparison of SAXS and linear dichroism measurements showed that regardless of preparation technique used nanotubes align preferentially parallel to polymer cylinders in SEBS composites. No preferred nanotubes` orientation was found in SIS composite showing that alignment is due to polymer matrix morphology and not to preparation technique. 
Discussion 
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