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arXiv · 1910.11641

Non-spherical nanoparticles in block copolymer composites: nanosquares, nanorods and diamonds

Javier Diaz·Marco Pinna·Andrei V. Zvelindovsky·Ignacio Pagonabarraga
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Abstract

A hybrid block copolymer(BCP) nanocomposite computational model is proposed to study nanoparticles(NPs) with a generalised shape including squares, rectangles and rhombus. Simulations are used to study the role of anisotropy in the assembly of colloids within BCPs, ranging from NPs that are compatible with one phase, to neutral NPs. The ordering of square-like NPs into grid configurations within a minority BCP domain was investigated, as well as the alignment of nanorods in a lamellar-forming BCP, comparing the simulation results with experiments of mixtures of nanoplates and PS-\textit{b}-PMMA BCP. The assembly of rectangular NPs at the interface between domains resulted in alignment along the interface. The aspect ratio is found to play a key role on the aggregation of colloids at the interface, which leads to a distinct co-assembly behaviour for low and high aspect ratio NPs.

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Javier Diaz, Marco Pinna, Andrei V. Zvelindovsky, Ignacio Pagonabarraga. 2019-10-25. Non-spherical nanoparticles in block copolymer composites: nanosquares, nanorods and diamonds. https://doi.org/10.1021/acs.macromol.9b01754

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