tailieunhanh - Báo cáo hóa học: " Nanoparticle Network Formation in Nanostructured and Disordered Block Copolymer Matrices"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Nanoparticle Network Formation in Nanostructured and Disordered Block Copolymer Matrices | Nanoscale Res Lett 2010 5 1712-1718 DOI s11671-010-9775-y NANO PERSPECTIVES Nanoparticle Network Formation in Nanostructured and Disordered Block Copolymer Matrices Michelle K. Gaines Steven D. Smith Jon Samseth Saad A. Khan Richard J. Spontak Received 23 July 2010 Accepted 23 August 2010 Published online 14 September 2010 The Author s 2010. This article is published with open access at Abstract Incorporation of nanoparticles composed of surface-functionalized fumed silica FS or native colloidal silica CS into a nanostructured block copolymer yields hybrid nanocomposites whose mechanical properties can be tuned by nanoparticle concentration and surface chemistry. In this work dynamic rheology is used to probe the frequency and thermal responses of nanocomposites composed of a symmetric poly styrene-b-methyl methacrylate SM diblock copolymer and varying in nanoparticle concentration and surface functionality. At sufficiently high loading levels FS nanoparticle aggregates establish a load-bearing colloidal network within the copolymer matrix. Transmission electron microscopy images reveal the morphological characteristics of the nanocomposites under these conditions. M. K. Gaines R. J. Spontak Department of Materials Science Engineering North Carolina State University Raleigh NC 27695 USA e-mail Rich_Spontak@ S. A. Khan R. J. Spontak Department of Chemical Biomolecular Engineering North Carolina State University Raleigh NC 27695 USA S. D. Smith Miami Valley Innovation Center The Procter Gamble Company Cincinnati OH 45061 USA J. Samseth Department of Process Technology SINTEF Materials Chemistry 7465 Trondheim Norway J. Samseth Akershus University College 2001 Lillestr0m Norway Present Address M. K. Gaines Electro-Optical Systems Laboratory Georgia Tech Research Institute Atlanta GA 30332 USA Keywords Block copolymer Colloidal network Nanostructured polymer Nanocomposite Silica Nanoparticles Fumed silica Colloidal silica Introduction .