Ternary Phase Diagram of the Triton X-100/Poly(acrylic acid)/Water System

The phase behavior of the Triton X-100/poly(acrylic acid) aqueous system within the entire range of surfactant concentration and up to 30 wt % polymer was examined at various temperatures. At 25 °C two isotropic solution phases (L1 and L2) and one hexagonal liquid crystalline phase form in the ternary system. The hexagonal liquid crystalline and the isotropic solution phases were characterized by means of PGSE-NMR, SAXS, and rheological measurements. The presence of the polymer changes the melting temperature rather than the SAXS lattice spacing of the hexagonal liquid crystalline phase. Self-diffusion studies in the isotropic solution region show that surfactant diffusion is slower when polymer is added. The obtained data show that surfactant and polymer associate; the polymer molecules are probably adsorbed on the surface of the surfactant aggregates.