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DOE OSTI · 22606251

Controlling block copolymer phase behavior using ionic surfactant

Ray, D.·Aswal, V. K.
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Abstract

The phase behavior of poly(ethylene oxide)-poly(propylene oxide-poly(ethylene oxide) PEO-PPO-PEO triblock copolymer [P85 (EO{sub 26}PO{sub 39}EO{sub 26})] in presence of anionic surfactant sodium dodecyl sulfate (SDS) in aqueous solution as a function of temperature has been studied using dynamic light scattering (DLS) and small-angle neutron scattering (SANS). The measurements have been carried out for fixed concentrations (1 wt%) of block copolymer and surfactants. Each of the individual components (block copolymer and surfactant) and the nanoparticle–surfactant mixed system have been examined at varying temperature. The block copolymer P85 forms spherical micelles at room temperature whereas shows sphere-to-rod like micelle transition at higher temperatures. On the other hand, SDS surfactant forms ellipsoidal micelles over a wide temperature range. Interestingly, it is found that phase behavior of mixed micellar system (P85 + SDS) as a function of temperature is drastically different from that of P85, giving the control over the temperature-dependent phase behavior of block copolymers.

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75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYAQUEOUS SOLUTIONSCOPOLYMERSETHYLENELIGHT SCATTERINGMICELLAR SYSTEMSNANOPARTICLESNEUTRON DIFFRACTIONNEUTRONSOXIDESPLASMA SWITCHESPOLYETHYLENE GLYCOLSPROPYLENESMALL ANGLE SCATTERINGSODIUMSPHERICAL CONFIGURATIONSULFATESSURFACTANTSTEMPERATURE DEPENDENCETEMPERATURE RANGE 0273-0400 K

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BibTeXRIS

Ray, D., Aswal, V. K.. 2016-05-23. Controlling block copolymer phase behavior using ionic surfactant. https://doi.org/10.1063/1.4947646

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