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Hierarchical self-assembling of thelechelic star polymers: from soft patchyparticles to diamond crystalsB. Capone 1 , F. Lo Verso 2 , C. N. Likos 1 , R. Blaak 11Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria2Institut für Physik, Johannes-Gutenberg-Universität Mainz, D-55099 Mainz, Germany.The production of self-assembling material, relieson building blocks simple enough to be reliablyproduced on a large scale. We propose di-blockcopolymer (telechelic) polymer stars as a verysimple and extremely tunable system that is able tohierarcically self assemble first into soft patchyparticles and then into complicated crystallinestructures as the diamond crystal. It will be shownthat the self aggregating patchy behavior can befully controlled by two parameters, which are thenumber of arms per star and the percentage ofattractive monomeric units in the tail of each of thearms. The low density conformational ”phase”diagram is extracted, both computationally andtheoretically, as a function of these parameters. Forlow densities the stars preserve their selfassembled structure and interact with one anotheras extremely flexible patchy particles. Onincreasing the density, they form percolatinggellike networks, and, for sufficiently highdensities, they are capable to sustain crystallinestructures. In particular we will demonstrate thatthese soft flexible patchy particles can assembleinto a mechanically stable diamond crystal, whichhas not been achieved so far at finite temperatureswith other models. Moreover our work provides anexplanation to experimental findings in [8, 9],where telechelic star polymer solutions were foundto crystallize into a diamond lattice for suitablevalues of number of arms and percentage ofattractive monomers.Fig. 1: A percolating gel formed by telechelic starpolymers with f = 5 arms and 60% of attractivemonomers per arm.Fig. 2: A mechanically stable diamond latticeformed by telechelic star polymers with 10 armsand 60% of attractive monomers.36