The assembly of rod-like particles by weak attractive inter-actions is important for the properties of several soft biological materials as wellas in tailoring the properties of colloidal gels in a variety of applications. Under-standing the link between the physicochemical parameters such as size and aspectratio, volume fraction, interparticle forces with the resulting microstructure andthe rheological response remains however challenging. It is often dicult to obtaina good control over these parameters due to the lack of suitable model systems.In the present work a model rod-like fd-virus particle has been surface modiedwith a thermoreversible polymer poly(N-isoproplyacrlyamide). The repulsive andattractive contributions to the overall interaction potential can be varied indepen-dently by changing the ionic strength and the temperature. The eects of thesechanges on the strength and structure of the gel have been studied near the geltransition using a combination of rheological and scattering measurements. Theresults show that for these thermoreversible 'sticky' rod systems, the variations ofthe structure in the gelled state are relatively weak, with the gel strength mainlybeing controlled by the relative magnitudes between the attractive and repulsivecontributions and the volume fraction, the anisotropic nature of the electrostaticinteractions seems to have a minor eect.
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