| Abstract
| - We present an experimental description of the dynamics of a dense colloidal suspension of model hairynanoparticles using dynamic light scattering. These colloids were obtained by cross-linking the poly(2-cinnamoylethyl methacrylate) cores of polystyrene-block-poly(2-cinnamoylethyl methacrylate), copolymermicelles. Because of their small size and the small spacing of their liquidlike structure, as detected withsmall-angle neutron scattering, these particles enable the systematic investigation of the low-scatteringwavevector (q) fraction of the dynamic structure factor (S(q,t)) away from the peak, which relates to theosmotic modulus of the suspension. The two relaxation processes contributing to S(q,t) are the fast cooperativediffusion of the concentration fluctuations (hair interactions) and the self-diffusion of the slightly polydispersecores (incoherent contribution). The former speeds up and loses intensity with increasing concentration,analogous to linear and hyperstar polymer solutions, whereas the latter slows down and exhibits virtuallyincreasing intensity with concentration as a consequence of the correlation hole at low q's, much like thehard sphere colloids. The study of these hairy particles contributes to the overall picture of the dynamicresponse of concentrated colloidal suspensions sterically stabilized by grafted macromolecules.
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