Abstract
Aqueous micellar solutions of ionic/neutral block copolymers have been studied by light scattering, small angle neutron scattering and small angle X-ray scattering. We made use of a polymer comprised of a short hydrophobic block (polyethylene-propylene) PEP and of a long polyelectrolytic block (polystyrene-sulfonate) PSSNa which has been shown previously to micellize in water. The apparent polydispersity of these micelles is studied in detail, showing the existence of a few large aggregates coexisting with the population of micelles. Solutions of micelles are found to order above some threshold in polymer concentration. The order is liquid-like, as demonstrated by the evolution with concentration of the peak observed in the structure factor (qpeak ∝ c1/3), and the degree of order is found to be identical over a large range of concentrations (up to 20 wt%). Consistent values of the aggregation number of the micelles are found by independent methods. The effect of salt addition on the order is found to be weak.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 77-86 |
| Number of pages | 10 |
| Journal | European Physical Journal B |
| Volume | 1 |
| Issue number | 1 |
| DOIs | |
| State | Published - 1998 |
Keywords
- 61.25.Hq Macromolecular and polymer solutions; polymer melts; swelling - 83.70.Hq Heterogeneous liquids: suspensions, dispersions, emulsions, pastes, slurries, foams, block copolymers, etc.