To promote network connectivity in colloidal rod suspensions, end with a tip

Colloidal gels formed from patchy rods provide a promising platform to design novel functional materials and formulations. Yet, the case for localized interactions at the rod tips remains relatively unexplored. Here we probe the structure and dynamics of such systems by means of coarse-grained computer simulations, and show that the emerging tipped gel networks are fundamentally different to uniform ones. Structurally, tipped networks are better connected, and, unlike in the uniform gels, the connectivity increases with the length of the constituent rods. The dynamics are also fundamentally different, with the gelation time in the tipped networks (contrary to the uniform gels) exhibiting an inverse relationship with rod length.