3D‐Positioning of Nanoparticles in High‐Curvature Block Copolymer Domains

Abstract

The defined assembly of nanoparticles in polymer matrices is an important precondition for next-generation functional materials.Here we demonstrate that adefined threedimensional nanoparticle assembly within the unit cells can be realized by directly linking the nanoparticles to blockc opolymers.W es howt hat for ar ange of nearly symmetric to unsymmetric blockc opolymers there are only two formed structures,ahexagonal lattice of P6/mmm-symmetry,where the nanoparticles are located in 1D-arrays within the cylindrical domains,a nd ac ubic lattice of Im3m-symmetry,w here the nanoparticles are located in the octahedral voids of aB CClattice,c orresponding to the structure of ferrite steel. We observe the blocklength ratio and thus the interfacial curvature to be the most important parameter determining the lattice type. This is rationalized in terms of minimal chain extension such that domain topologies with large positive curvature are highly preferred. Already volume fractions of only one percent are sufficient to destabilize al amellar structure and favor the formation of highly curved interfaces.T he study thus demonstrates how nanoparticles can be located on well-defined positions in three-dimensional unit cells of blockc opolymer nanocomposites.T his opens the way to functional 3D-nanocomposites where the nanoparticles need to be located on defined matrix positions.