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An L3-phase is observed for the first time in a ternary phase diagram of a Ca-salt of an α-sulfonated alkyl fatty acid methyl ester, the cosurfactant (2-ethylhexyl)monoglyceride and water. As for other ternary surfactant/cosurfactant systems, the L3-phase occurs with increasing cosurfactant/surfactant ratios after the Lα-phase. Some properties of the newly observed L3-phases are the same as for other known L3-phases. It is a low viscosity, optically isotropic fluid with a low flow birefringence. The time constants τ of the electric birefringence results scale with τ ∼ Ø-3. Its conductivity is very much higher than that of the neighboring Lα-phase, but there are some marked differences from known L3-phases. This novel L3-phase is thermodynamically stable despite ionic structure of the surfactant. We found no two phase region between the Lα and the L3-phase, and the L3-phase is stable over a wide cosurfactant/surfactant ratio between one and two. In SANS measurements it shows a broad correlation peak that occurs at about the same position as the sharper peak in the Lα-phase. The structure of the L3-phase is demonstrated by FF-TEM micrographs.

ABSTRACT:The adsorption of acrylic polyampholytes on fiberglass reinforced plastics (FRP) was investigated using random copolymers derived from (dimethylamino)ethyl methacrylate (DM), methacrylic acid, and t-butyl methacrylate (t-BMA). The effect of the copolymer structure changes on the adsorption and the interactions between the copolymers and the surface were assessed using -potential and contact angle measurements, NMR, and ESCA. The copolymer having the composition of 58 mol % pDM, 38 mol % pMMA, and 4 mol % pt-BMA was adsorbed on the FRP surface at pH 7, and it formed the highest hydrophilic surface among the tested copolymers. An analysis by use of atomic force microscope revealed that the copolymer afforded a uniform 4 -6 nm thick coverage on the FRP. We concluded that the interactions between the copolymer's cationic sites and the anionic FRP surface are important as well as the hydrophobic interaction for adsorption. Furthermore, it is suggested that the hydrophilicity of the copolymer's adsorbed surfaces is related to the density of the copolymer's anionic sites. These results indicate that the ampholytic structure of the polymers would be essential for the surface modification on the FRP. The effect of functional groups of surfaces on the acrylate adsorption was also assessed using surface plasmon resonance.

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