Colloidal design Building, bending and breaking

Colloids currently form one of the most exciting platforms for developing self-assembling designer materials. Such materials mimic biological matter in their bottom-up hierarchical organization, and in the way they derive function from dynamic mechanical properties. Recent breakthroughs in synthesis have yielded colloidal building blocks with precise control over shape and surface properties. However, their assembly in functional architectures remains challenging, requiring interaction control, fundamental understanding of in and out-of-equilibrium self-assembly pathways, and a deeper knowledge of micromechanical behavior.
This thesis presents a colloidal system for directed and controlled self-assembly, using temperature tunable critical Casimir forces and patchy particles, which have a heterogenous surface with patches of tunable size. We show that these particles self-assemble in different architectures ranging from various small scale well-defined structures to sample-spanning networks. In addition, these architectures are put to the test by a series of micromechanical studies on simple basic structures: Straight colloidal chains. Using optical tweezers and thermally induced bending fluctuations, a rich semiflexible mechanics is revealed, which involves stochastic buckling instabilities, viscoplastic effects and fracture.