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Structure factor of polymers interacting via a short range repulsive potential: application to hairy wormlike micelles

G. Massiera·E. Pitard·L. Ramos·C. Ligoure
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Abstract

We use the Random Phase Approximation (RPA) to compute the structure factor, S(q), of a solution of chains interacting through a soft and short range repulsive potential V. Above a threshold polymer concentration, whose magnitude is essentially controlled by the range of the potential, S(q) exhibits a peak whose position depends on the concentration. We take advantage of the close analogy between polymers and wormlike micelles and apply our model, using a Gaussian function for V, to quantitatively analyze experimental small angle neutron scattering profiles of semi-dilute solutions of hairy wormlike micelles. These samples, which consist in surfactant self-assembled flexible cylinders decorated by amphiphilic copolymer, provide indeed an appropriate experimental model system to study the structure of sterically interacting polymer solutions.

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G. Massiera, E. Pitard, L. Ramos, C. Ligoure. 2003-01-09. Structure factor of polymers interacting via a short range repulsive potential: application to hairy wormlike micelles. https://doi.org/10.1103/physreve.68.021803

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